Build the EchoLedger - per-file write provenance for announcements

User-ruled 2026-07-29: the ledger builds now in base, pre-release
(DESIGN/02 - Components - EchoLedger; DESIGN/10 - Live board
announcements). Receipts drop inside BoardWriter's four disk primitives
(atomic replace, folder move, removal, attachment copy) into a @TaskLocal
ledger that BoardStore.performWrite binds for the bracket's duration -
no call-site bookkeeping, and performWholesale deliberately binds
nothing per 02's bracket exemption. Classification is a pure function of
two snapshots: an item whose folder, index.md bytes, or attachment
listing differs is an observed change; disk matching the receipt is
app-mediated (receipt consumed), no receipt or mismatch is foreign.
Byte-identical foreign overwrites classify app-mediated (unobservable,
accepted); a foreign edit over a fresh app write classifies foreign.

The announcer now consumes per-file facts on every reload origin - the
WatchOrigin gate is gone (ReloadFacts.origin removed outright; nothing
read it after the gate fell). Reconciling sweeps announce their
receipt-less findings as foreign, closing both interim holes
(debounce-window absorption, reconcile silence). The vanishing-focus
rung gates on the ledger too: "deleted externally" would be a lie about
an app-mediated delete, and the subject's own verdict decides.

Divergence flagged: attachment imports hash the landed file right after
FileManager.copyItem rather than during the copy (the bytes do not
stream through the app); an unreadable read-back records nothing, the
direction that biases toward foreign.

30 ledger tests added, announcer suite reworked to the ruling. 1638
green on both schemes.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

README.md

@@ -10,7 +10,7 @@ Lanework is in early development. This list tracks what has actually shipped and
 
 - **Storage contract, read side** — frontmatter engine with a byte-perfect round-trip guarantee (unknown keys, comments, and formatting survive every rewrite; duplicate keys read last-wins; wrong-type scalars coerce read-side), gapped fractional ordering (Ranks), and a fail-fast board loader with UUID-gated level detection, warning-collecting skips, and a reserved `.trash/` container read by the very same card parse the lanes use — pinned by a golden fixture suite of 18 on-disk boards.
 - **Storage contract, write side** — BoardWriter turns every mutation into an atomic temp-file+rename over exactly the files it touches: creates mint lowercase-UUIDv4 identities and `.kanban` packages; moves keep the UUID (with per-folder collision repair at the cross-board import boundary); copies mint fresh identities at every level; deletes move a card's folder into the board's reserved `.trash/` at a caller-minted top rank, restore is the ordinary move back out, and purge is physical; attachment imports never overwrite and never refuse (Finder-style renames). Every app write stamps `modified`, clears `modified-by`, and preserves everything it didn't change byte-for-byte; readable-but-uneditable frontmatter shapes refuse loudly instead of corrupting. Strays are preserved verbatim everywhere with exactly one carve-out: a loose *file* dropped beside a card's `index.md` belongs in that card's `attachments/`, so the app moves it there — Finder-renamed on collision, byte-faithfully, without touching `index.md` — and says so in a dismissable warning row naming the card and the files. Detection stays read-only in the loader; the move is an ordinary bracketed write that waits out the read-only lock and never retries a failure in a loop. Stray *folders*, symlinks, and everything at board or lane level keep the verbatim posture untouched, and a paste normalizes at the import boundary so a pasted card lands already tidy.
-- **Live store** — every open board is one shared, watched, in-memory snapshot: an FSEvents folder watcher (debounced, `.git`-filtered, origin-reconciling) drives whole-tree reloads with a generation guard and single-flight coalescing; write brackets suppress self-echo; a file-identity-keyed store registry refcounts stores and watchers across windows and absorbs root renames via bookmark re-resolution (a vanished root locks the board and watches for its return); plus the board registry (recents, bookmarks, cached counts), the banner center's single precedence order, the dirty-buffer guard, and transient UI state.
+- **Live store** — every open board is one shared, watched, in-memory snapshot: an FSEvents folder watcher (debounced, `.git`-filtered, origin-reconciling) drives whole-tree reloads with a generation guard and single-flight coalescing; write brackets suppress self-echo, and a per-board **write-provenance ledger** — in-memory, dying with the session — records a content hash, an absence marker or an old→new pair for every file the app writes, so a landing reload can tell its own echo from an outside edit file by file (final content decides: byte-identical is the app's, one byte different is somebody else's); a file-identity-keyed store registry refcounts stores and watchers across windows and absorbs root renames via bookmark re-resolution (a vanished root locks the board and watches for its return); plus the board registry (recents, bookmarks, cached counts), the banner center's single precedence order, the dirty-buffer guard, and transient UI state.
 - **Window architecture** — the three window types and their lifecycle: a welcome window (below), one board window per root (per-board frame memory, repositioned onto a live screen), and at-most-one card window per card (last-used size, cascaded, then per-card frame memory once you've placed one; follows its card across lanes; dismisses the moment its card leaves the board — into the trash, with its deleted lane, purged, or moved to another board). Closing a board window or quitting runs one strict close flush — card sessions end, pending work drains, the registry is stamped — before the store tears down; launch restores the boards whose open-now flags survived quit (or crash), a preference gating only whether the flags are consulted.
 - **The board** — every lane always on screen, the window's width dividing across the lanes' width units with no horizontal scroll: cards flow into as many interior masonry columns as a lane is wide, a right-edge drag resizes between whole units by growing the *window* (snapping at the gap with release hysteresis, hard-stopping at the screen with rubber-band feedback), and ⌥⌘→/⌥⌘← re-divide the existing width instead. Lane chrome is a per-lane SF Symbol (unknown names fall back leniently), title or untitled placeholder, a card-count badge that counts exactly what's rendered, and a new-card button — the whole title bar doubling as the drag surface, a plain click selecting the lane and movement carrying it away.
 - **Card faces** — a card reads as a leading SF Symbol, its title (or a quiet untitled placeholder), and a quiet paperclip when it has attachments — title-only by design, no body excerpt. Colour is an edge accent rather than a fill: `background` paints a stripe down the card's left edge and `iconColor` tints the symbol, both written as a kebab-case palette name (12 icon tints, 12 backgrounds) or a `#RRGGBB[AA]` hex. Everything degrades rather than complains — an unreadable colour simply doesn't paint, and the value stays on disk exactly as written. Each card's snapshot carries its attachment names, listed flat and in Finder order (top-level files only; subfolders, hidden files, and symlinks are preserved but never surfaced). A card has one presentation: selection changes only its styling, never its geometry, so the masonry never reflows on a click — the paperclip chip is the face's whole attachment story, and viewing the files themselves is the card window's job.
@@ -48,7 +48,7 @@ Lanework is in early development. This list tracks what has actually shipped and
 
 - **The agent guide** — every board root carries a `CLAUDE.md` the app writes and keeps current: a condensed, agent-facing rendition of the schema — the folder layout, ordering arithmetic, creating and moving cards, the `.trash/` convention, `attachments/`, `modified-by` self-stamping, the colour and icon palettes, and the git etiquette — so any file-capable agent dropped into the folder already knows how to work the board. It is app-owned and version-gated by a marker in its first line: rewritten when missing or older, left byte-for-byte alone when current or newer, and re-checked on every reload, so a guide deleted or rolled back from outside heals by itself. A `CLAUDE.md` that isn't the app's is never clobbered — it moves to `CLAUDE.user.md` (the user's own extension point, which the app otherwise never touches), and if that name is taken the app simply doesn't write a guide. A symlink or folder wearing the name is left alone, and a board on a read-only volume is skipped in silence: the guide is a courtesy and never an interruption.
 
-- **Accessibility** — the board is a real VoiceOver surface, not a grid of unlabelled rectangles: lanes are containers read as "⟨title⟩, lane, N cards" (the count is the filter's, like the visible badge), each card is one flattened element carrying its title, its attachment count and its cut-pending state, and traversal follows card `order` rather than masonry column position. VO-Space toggles selection through the same funnel a ⌘-click uses, context-menu rows double as custom actions, lane titles are headings for the rotor, and the trash column pins last. A **live board announces itself**: a foreign edit lands as one polite, non-interrupting digest per reload — "Board changed: 2 cards edited, 1 card added" — while the app's own writes stay silent, and a card that disappears under the cursor is named rather than merely lost ("Card 'Fix login' was deleted externally"), with focus recovering to its lane; when the lane went too, the announcement names the *lane* and its count and focus walks up then sideways to whatever now holds its position. Bracketed operations say one thing at completion and never their internal churn, and the banner strip is an announced element in its own right — the read-only lock and reload breakage speak when they appear and when they clear. **Every size in the app is relative**: there is not one hard-coded point size left — the card face, the lane header, the masonry, the style editor's wells and every window's floor derive from the system body font, so the whole board grows with the system text size while the no-horizontal-scroll rule holds (the lanes compress, the strip never scrolls) and titles keep truncating gracefully. The system's visual accommodations are wired throughout: **Increase Contrast** thickens every border and selection ring and gives card and lane plates an outline they don't otherwise have, **Reduce Transparency** turns the transient search bar's glass and the trash column's washes solid, and **Reduce Motion** has a variant for every animated surface in the app — movement goes instant, appear/disappear goes crossfade, uniformly, the live-reload seam included. **A coloured board computes its own text colour.** The board background is the one surface the app lets a colour sit behind text, so the ink is chosen rather than assumed: WCAG relative luminance against the ≥ 4.5:1 threshold, with an `#RRGGBBAA` value composited over the window background of the appearance you are actually in — so lane and trash headers take light or dark glyphs on their own and re-decide the moment you switch to Dark Mode. One path serves both halves of the styling vocabulary: the twelve palette wells are pinned by a test that checks the ink the app *picks* for each of them in both appearances (a dark palette board is now readable in Light Mode, which it was not), and a hand-written hex — which stays fully honoured from disk — gets the identical computation as it renders. Nothing is ever said by colour alone (selection is a ring plus a trait, a cut card is dimmed plus "cut, pending paste", the trash header is hatched plus labelled, a mixed batch reads "mixed"), and under **Full Keyboard Access** the board is a single visible tab stop with the arrow grammar inside it while every control around it — lane buttons, popovers, the style grids, welcome rows, template tiles — is Tab-reachable, arrow-navigable and labelled.
+- **Accessibility** — the board is a real VoiceOver surface, not a grid of unlabelled rectangles: lanes are containers read as "⟨title⟩, lane, N cards" (the count is the filter's, like the visible badge), each card is one flattened element carrying its title, its attachment count and its cut-pending state, and traversal follows card `order` rather than masonry column position. VO-Space toggles selection through the same funnel a ⌘-click uses, context-menu rows double as custom actions, lane titles are headings for the rotor, and the trash column pins last. A **live board announces itself**: a foreign edit lands as one polite, non-interrupting digest per reload — "Board changed: 2 cards edited, 1 card added" — while the app's own writes stay silent. Which is which is decided **per file by the write-provenance ledger**, never by which kind of reload delivered it: a reconciling sweep on wake or reactivation announces whatever changed in the blind window (the app never vouches for changes it didn't witness), and a foreign edit that lands on a file the app had just written is still announced. A card that disappears under the cursor is named rather than merely lost ("Card 'Fix login' was deleted externally"), with focus recovering to its lane; when the lane went too, the announcement names the *lane* and its count and focus walks up then sideways to whatever now holds its position. Bracketed operations say one thing at completion and never their internal churn, and the banner strip is an announced element in its own right — the read-only lock and reload breakage speak when they appear and when they clear. **Every size in the app is relative**: there is not one hard-coded point size left — the card face, the lane header, the masonry, the style editor's wells and every window's floor derive from the system body font, so the whole board grows with the system text size while the no-horizontal-scroll rule holds (the lanes compress, the strip never scrolls) and titles keep truncating gracefully. The system's visual accommodations are wired throughout: **Increase Contrast** thickens every border and selection ring and gives card and lane plates an outline they don't otherwise have, **Reduce Transparency** turns the transient search bar's glass and the trash column's washes solid, and **Reduce Motion** has a variant for every animated surface in the app — movement goes instant, appear/disappear goes crossfade, uniformly, the live-reload seam included. **A coloured board computes its own text colour.** The board background is the one surface the app lets a colour sit behind text, so the ink is chosen rather than assumed: WCAG relative luminance against the ≥ 4.5:1 threshold, with an `#RRGGBBAA` value composited over the window background of the appearance you are actually in — so lane and trash headers take light or dark glyphs on their own and re-decide the moment you switch to Dark Mode. One path serves both halves of the styling vocabulary: the twelve palette wells are pinned by a test that checks the ink the app *picks* for each of them in both appearances (a dark palette board is now readable in Light Mode, which it was not), and a hand-written hex — which stays fully honoured from disk — gets the identical computation as it renders. Nothing is ever said by colour alone (selection is a ring plus a trait, a cut card is dimmed plus "cut, pending paste", the trash header is hatched plus labelled, a mixed batch reads "mixed"), and under **Full Keyboard Access** the board is a single visible tab stop with the arrow grammar inside it while every control around it — lane buttons, popovers, the style grids, welcome rows, template tiles — is Tab-reachable, arrow-navigable and labelled.
 
 ## Development