Define how non-snapshot files commit — whole-root staging, path-shaped events

The composer was a pure snapshot diff while the repo tracked files outside
the model (agent guide, strays, .gitignore), leaving stray-only windows
uncommittable and the guide's own subject underivable. Settled: the
committer stages the whole root with the tree as its commit condition; the
composer also receives the changed-path list, composing "Update agent
guide (vN)" (version from the marker line) and "Update '<path>'" events
that ride as body bullets under model-event subjects; attribution falls
out of the path-keyed EchoLedger.

Claude-Session: https://claude.ai/code/session_01HJ7PhFNmQ19bvy9RMD6GSb

DESIGN/06-history-undo.md

@@ -30,6 +30,7 @@ The pathfinder's message engine carries over as the model — it is what earns t
 - **Pure snapshot diff, no write-site tagging.** Messages compose at commit time from a structural diff of two board snapshots (last-committed vs. current) — never by intercepting operations. Items match by id across the *whole* board, so a lane change is distinguishable from delete+add and a cross-lane move reads as a move. Bookkeeping — `order` changes that preserve sibling sequence (a renumber's rescale — 01-storage-format.md), `modified`/`created` — produces no events: a diff touching only those composes nothing. Sequence is what the diff compares, not raw `order` values: an order change that *repositions* an item among its siblings composes Reorder, so a foreign writer's single-file reorder still reads as one. A midpoint-exhaustion renumber batches with the insert or move that triggered it, so its commit reads as that event.
 - **Vocabulary**: Add / Delete / Move / Rename / Edit / Restyle / Resize / Reorder over cards, lanes, and the board, plus Attach / Remove for attachment files ("Move card 'Fix login' to Doing", "Rename lane 'Todo' → 'Doing'"), plus the trash pair (settled) — **Restore** and **Permanently delete** — distinguished by diff shape alone, keeping the composer a pure snapshot diff: `deleted:` appearing is Delete (the tombstone), `deleted:` *clearing* is Restore ("Restore card 'X'" — Put Back, drag-to-restore), and an item *leaving the tree entirely* is Permanently delete ("Permanently delete card 'X'" — Delete Immediately, Empty Trash, and any foreign hard removal, which the shape rule catches and describes accurately for free). The trail thereby tells moved-to-trash from gone-forever — the distinction Deleting never forgets (below) asks users to learn. Plural folding applies as usual: Empty Trash reads "Permanently delete 12 cards", cleanly distinct from a multi-select ⌫'s "Delete 12 cards". One commit per debounce window: a single event is the subject (with a detail body where one helps); several events of one kind fold into a plural subject, with shared destinations preserved ("Move 3 cards to Done"); genuinely mixed windows fall back to "Update board" — always with a bulleted body naming every event, so the oneline log stays scannable and the full message stays complete.
 - **Implied events don't steal the subject**: deleting a lane with five cards reads "Delete lane 'X'" with the card deletions as body bullets — not "Update board".
+- **Non-snapshot files commit too** (settled — the repo tracks more than the model: the agent guide, `CLAUDE.user.md`, the seeded `.gitignore`, and strays at every level): the committer **stages the whole board root** — whatever `git status` shows, `.gitignore` respected — and its commit condition is the *tree*, not the snapshot diff, so a stray-only window commits rather than leaving the tree dirty (a permanently dirty stray would break branch switch's cannot-fail-dirty guarantee and void flush-before-overwrite for every file the model can't see). The composer's input extends accordingly: beside the snapshot diff it receives the changed-path list, and non-snapshot paths compose **path-shaped events** — `CLAUDE.md` composes "Update agent guide (vN)", the version read from the guide's marker first line (a pure function of file content, *not* write-site tagging — the no-interception rule stands); any other non-snapshot path composes "Update '⟨path⟩'", folding plural ("Update 3 files"). Model events keep the subject when present; non-snapshot changes then ride as body bullets — recorded, never silently absorbed under an unrelated subject. Attribution needs no new rule: the EchoLedger (02-architecture.md) is path-keyed, so the app's guide write classifies app-mediated by its receipt (the mechanism behind the guide-attribution exception below) and a stray edit classifies foreign, the two-commit split applying per file as everywhere else.
 - **Titles truncate in subjects only** (~40 chars, keeping `git log --oneline` sane); body lines carry full titles. An untitled item reads "(untitled)" — never a bare `""` (a pathfinder edge fixed, not carried). Undo/redo restores commit as "Undo: ⟨subject⟩" / "Redo: ⟨subject⟩"; the undo-menu labels are the *crossed* commit's subject, so labels never nest.
 
 **The external gap, closed** (the pathfinder weakness this section exists to fix): the composer is origin-agnostic, but external writers routinely touch what the pathfinder's diff never modeled — `labels`, `assignees`, `due`, custom frontmatter keys — so their commits degraded to a generic fallback even though the attribution machinery knew plenty. The rewrite:

DESIGN/08-agent-integration.md

@@ -28,7 +28,7 @@ Mechanics: version marker in the first line (`lanework-agent-guide vN`); rewritt
 
 **`CLAUDE.user.md`** is the user's extension point: an optional, user-authored file at board root carrying board-specific agent instructions. The generated guide tells agents to read it when present, so it lands in agent context without the app ever touching it — the app never writes, upgrades, or validates it.
 
-On git boards, a guide write rides the normal watcher → auto-commit path with an honest message ("Update agent guide (v3)"), not "External edit" (06-history-undo.md).
+On git boards, a guide write rides the normal watcher → auto-commit path with an honest message ("Update agent guide (v3)"), not "External edit" (06-history-undo.md ▸ Commit messages — the non-snapshot-files rule: the committer stages the whole root, and the composer reads the subject's version from the guide's marker line, a pure function of file content).
 
 ## Agent conventions worth specifying (new in the rewrite)