Closes the gap found at m10: enterUnwritableLock existed with zero call
sites. WritabilityProbe classifies the cause volume-first - a board on a
read-only DMG is also permission-denied by access(2), and "you don't
have permission" would send the user to a Get Info panel that cannot
help - with a pure classify(volumeIsReadOnly:isWritable:) truth table
and a two-syscall probe that rebuilds its URL to defeat NSURL resource
caching. ReadOnlyLockReason.unwritableLocation now carries the cause;
BannerCenter phrases the two ("this board's volume is read-only" vs
"you don't have permission to change this folder").
The probe wires once in BoardStoreRegistry.acquire, immediately after
the store loads - every open path funnels through it, and running
before the loose-file relocation and agent-guide hooks makes the
skipped-with-log guide write true by construction (its isWritableFile
pre-check demotes to second line of defense). The board still opens:
lock, not refusal.
The reconciling re-probe is now symmetric per 02's settled text - a
volume gone read-only mid-session raises the lock at the next probe
(sibling locks settle first, so a root returning read-only lands the
honest lock); the stale "deliberately one-way" comment and its pinning
test are gone. Save as Template's carve-out predicate extracted to a
testable allowsSave (behavior unchanged); Duplicate stays disabled.
11 tests added. 1649 green on both schemes.
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY
The editing surface: the same hosted TextKit-1 text view gains an
editable branch with a per-keystroke line-scanner highlighter — chosen
over a parser re-parse because a mid-typing buffer is usually invalid
Markdown and 05 wants the delimiters themselves dimmed; apply only sets
attributes, so presentation-never-transforms is structural. Saves ride
a ~700ms injectable debounce through BoardWriter.writeBody —
toggleTaskMarker's idiom widened to the body span, frontmatter bytes
untouched, refusing to write when disk already holds that body, which
enforces all three gates (untouched, reverted, echo) at the layer that
owns the bytes with one isDirty predicate above it. Mode grammar lands
whole: ⌘E toggles with a checkmark, Return in Preview enters, Escape
returns, and every flip flushes first; window close flushes through
the existing retry/save-copy/discard modal, and the dismissal flush
deliberately reaches a tombstoned card. Dirty-buffer-wins: disk always
follows the snapshot, the buffer only when clean, both surfaces render
the buffer. Undo is the editor's own session-scoped NSUndoManager;
endEditSession names the pro-m1 one-commit-per-session boundary.
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY
rzen