fix v1.43.0: external audit P0 — data loss, split geometry, auth, dialog zombies

L2 (silent data loss): debounce gains flush()/pending(); _reloadConfigOnly
flushes a pending write and defers while one is in flight; conflict path
forces; failed reload now toasts instead of an empty catch; teardown flushes.

G1 (split corruption): same-edge cuts carve the niche properly instead of
walking the outline twice; partition invariant (parts sum to the original)
rejects anything else; +1 unit test covering 5 niche shapes and both legacy
cut shapes.

B1 (unauthenticated content): plans and marker files move to
HouseplanContentView (/api/houseplan/content/..., requires_auth); only the
card bundle stays static; contentUrl() rewrites legacy URLs on read (no
storage migration); repairs.py accepts both prefixes; +1 unit test.

L3 (dialog zombies): all four save catch-blocks guard against a closed
dialog; the card no longer blanks when a save fails after Esc.

smokes: smoke_save_race, smoke_dialog_zombie; docs (TESTING/CHANGELOG/
ARCHITECTURE incl. the optimistic-UI note) same-commit

docs/ARCHITECTURE.md

@@ -255,3 +255,20 @@ more specific tier overrides the more general one; "unset" always means
 The UI will later be unified around this model; until then each tier keeps its
 own dialog (general settings gear / space gear / room-card gear / marker
 dialog).
+
+
+## Audit follow-ups (2026-07-27)
+
+- **Content is authenticated.** `/houseplan_files/…` now serves ONLY the card
+  bundle (a Lovelace resource must be public). Plans and marker files go
+  through `HouseplanContentView` (`/api/houseplan/content/<plans|files>/…`,
+  `requires_auth`). `contentUrl()` rewrites legacy stored URLs on read, so no
+  storage migration is needed. Static paths cannot be unregistered — the old
+  routes survive until the next HA restart.
+- **Optimistic UI, stated explicitly (audit L7).** `_serverCfg` is mutated in
+  place before a fallible save in ~22 places and there is no rollback: after a
+  rejected save the UI shows the edit until the next reload. This is a
+  deliberate optimistic-UI choice, not drift. Paths where it is unacceptable
+  need their own rollback.
+- **Split invariant.** `splitRoomPath` guarantees a partition: the two parts'
+  areas sum to the original (within epsilon) or the cut is rejected.

docs/CHANGELOG.md

@@ -1,5 +1,32 @@
 # Changelog
 
+## v1.43.0 — 2026-07-27 (external audit: P0 fixes)
+
+An external code audit of v1.41.1 found four critical issues. All four are fixed
+and covered by regression tests.
+
+- **Silent data loss on save (L2).** A debounced config write read the config at
+  fire time, so a `houseplan_config_updated` event arriving in between replaced
+  it and the user's edit vanished with no error — reproducible in a single tab.
+  The debounce now supports `flush()`/`pending()`, a reload flushes the pending
+  write first and defers while a write is in flight, and a failed reload finally
+  reports instead of staying silent.
+- **Split corrupted room geometry (G1).** A cut starting and ending on the SAME
+  wall (carving a niche — a natural action) produced two overlapping,
+  self-intersecting rooms whose areas summed to twice the original, and the
+  overlap guard did not catch it. Same-edge cuts now carve the niche correctly,
+  and a partition invariant (parts must sum to the original) rejects anything
+  else.
+- **Plans and uploaded files were served without authentication (B1).** Anyone
+  who could reach the HA endpoint could fetch floor plans and attached manuals
+  without logging in. They are now served by an authenticated view; stored
+  legacy URLs are rewritten on read, so nothing breaks. **The old public paths
+  disappear after a Home Assistant restart.**
+- **Dialogs could resurrect and blank the card (L3).** Closing a dialog while
+  its save was in flight, on a failed save, spread `null` into a truthy husk;
+  the renderer then threw and the card went blank until reload. Guarded in all
+  four save routines; the error toast still fires.
+
 ## v1.42.2 — 2026-07-26
 - Touch devices no longer pop hover tooltips on every tap (field feedback:
   "extra labels appear and get in the way on a tablet"). Hover tooltips are

docs/TESTING.md

@@ -140,6 +140,19 @@ Run the *core flows* (marked ★ below) in each environment at least once per mi
       (explicit ripple color still wins); off/white lights unchanged [auto]
 - [ ] Alarm pulse (v1.27.0): leak/smoke/gas/CO/siren in 'on' pulse a red ring over any
       display mode; clears on 'off'; unavailable never alarms [auto]; reduced-motion static
+- [ ] Save race (v1.43.0, audit L2): make a markup edit, then press Save in any
+      dialog within 500 ms (or let another client save) — the markup edit must
+      survive and reach the server; a failed reload now shows a toast [auto]
+- [ ] Niche split (v1.43.0, audit G1): a cut that starts AND ends on the same
+      wall carves a niche; the two parts' areas must sum to the original (the
+      invariant is enforced in code and asserted for every split test) [auto]
+- [ ] Authenticated content (v1.43.0, audit B1): plan images and marker files
+      are only reachable through /api/houseplan/content/… with a session; the
+      old /houseplan_files/plans|files paths return 404 after a restart; old
+      stored URLs keep working (rewritten on read) [auto+manual]
+- [ ] Dialog zombies (v1.43.0, audit L3): close a dialog (Esc) while its save is
+      in flight and let the save fail — the dialog stays closed, the card keeps
+      rendering, the error toast still fires [auto]
 - [ ] No hover tooltips on touch (v1.42.2): on hover-less devices (tablets,
       phones) taps never pop the room/device tooltip — the data lives in room
       cards and long-press; desktop hover tooltips unchanged [auto]