feat(lists): manage lists in the app, and fix four store defects

Owning the store left a fresh install with no lists and no way to make
one, so no way to save a task. The seam gains updateList/deleteList
beside createLocalList on both paths — the External one addresses the row
as its own account's sync adapter, the only caller the provider lets
write tasklists. ListEditorSheet is the family's full-screen sheet: name
field, a 12-colour palette, and a destructive row behind a confirm when
editing. Entry points are a "New list" row under the home Lists section,
an empty state with a create button, and the home FAB switching to "New
list" while there are none. Deleting takes the list's tasks with it and
is offered only for device-only lists.

Four defects a review of the branch turned up:

- completing one occurrence closed the whole series — setCompleted wrote
  the master, the row TaskDao.tasks filters on. setCompletedInstance
  forks a RECURRENCE-ID override the way updateInstance does; phase 2
  always specified this, only the edit half had it
- the expansion ceiling was spent on the past, so a sub-daily series
  stopped expanding months before today and never reached Today or
  Upcoming
- an imported START-referenced reminder fired off DUE, because the seam
  collapsed alarms to a bare minute count. TaskReminder carries the
  anchor now
- registerObserver bound a live flow to whichever store was active at
  subscription, so a Settings store switch left every screen listening to
  the store it had stopped reading

docs/ROADMAP.md

@@ -207,6 +207,18 @@ most of it broken, absent or unusable. Reasoning in
 - ✅ Fallout: `ReminderScheduler.sync()` gated on `resolve() != null`, which is
   what `OWN` returns, so no due reminder armed in the default mode. It now gates
   on `ProviderResolver.canReadStore()`, with tests.
+- ✅ Fallout, second pass — four defects a review of the branch turned up:
+  **completing one occurrence closed the whole series** (`setCompleted` wrote the
+  master, which is the row `TaskDao.tasks` filters on, so every occurrence left
+  every list); the **expansion ceiling was spent on the past**, so a sub-daily
+  series stopped expanding months before today and never reached Today or
+  Upcoming; an imported **`START`-referenced reminder fired off `DUE`**, because
+  the seam collapsed alarms to a bare minute count; and `registerObserver` bound
+  a live flow to whichever store was active at subscription, so a Settings
+  store switch would have left every screen listening to the store it had
+  stopped reading. `setCompletedInstance` now forks a `RECURRENCE-ID` override
+  the way `updateInstance` does — phase 2 always specified this, only the edit
+  half had it.
 - ⬜ **Run the instrumented suite on a device.** Six classes — the Room seam, the
   DAOs, the import, the migration harness, the restore path and the performance
   check — all compile and none has ever executed. Everything load-bearing about
@@ -215,6 +227,21 @@ most of it broken, absent or unusable. Reasoning in
   v0.3.2 APK with seeded data landing every task, list and reminder.
 - ⬜ Per-locale release notes for the dropped authority and permissions.
 
+### ✅ Managing lists in the app
+Owning the store made this mandatory: there is no longer a provider app to
+create a list in, so a fresh install had no lists, no way to make one, and
+therefore no way to save a task. The seam gained `updateList` / `deleteList`
+beside the existing `createLocalList`, implemented on both the Room and the
+External path (which addresses the row as its own account's sync adapter, the
+only caller the provider lets write `tasklists`).
+- ✅ `ListEditorSheet` — the family's full-screen sheet with a name field, the
+  12-colour palette and, when editing, a destructive row behind a confirm.
+- ✅ Entry points: a "New list" row under the home Lists section, a real empty
+  state with a create button, and the home FAB switching to "New list" while
+  there are none. Editing is the pencil in a list's own top bar.
+- ✅ Deleting a list deletes its tasks — `tasks.list_id` cascades — and is
+  offered only for device-only lists; an account's collection is its server's.
+
 ---
 
 ## Open decisions / to verify