Separate user intent from planner output via day assertions

The calendar mixed two kinds of truth in one table. `planned_leave_day` was
simultaneously the allocator's output cache, the user's override store
(`is_pinned`, plus ad-hoc rows with no `wish_id`), and the resource ledger that
analytics and the age-4 maths read. The planner therefore had to ask "am I
allowed to touch this row?" on every sync, and got it wrong at the edges.

Every user assertion is now one `day_assertion` row — a concrete `day_type`
replaces a pinned day, a row with no `wish_id` replaces an ad-hoc day, and
`day_type='none'` replaces `planned_day_exclusion`. `planned_leave_day` becomes
purely derived with a single writer, and `PlanningService.pinned_keys()` is the
single answer to "is this day pinned", used by the allocator's loader, by
`sync_plan` and by the read router alike.

On top of that, every calendar band is now a real event: an ad-hoc band opens
the same full editor as a wish-backed one and saving it promotes it to a
`LeaveWish`, so it can be named, repeated yearly, assigned to either or both
parents, and handed to the planner. "Planering" is a `moveable` toggle plus a
from/to month bound plus a separate lock/unlock action on the days themselves,
replacing a three-rung ladder whose "planner decides" rung set a search window
equal to the drawn dates and so could never move anything.

Bugs found and fixed along the way:

- The plan erased its own history. Fixed windows clip to today, so an elapsed
  auto-placed day fell into `stale_keys` and was deleted on the next sync —
  and a background sync runs on every workspace load. Past rows are now frozen
  and counted as spent.
- Migration 010's downgrade silently destroyed every pinned day and exclusion
  (`is_pinned` returned as DEFAULT 0, the exclusion table came back empty,
  exit 0, no warning). It now reconstructs both from `day_assertion`, and 009
  itemises what it cannot recover before dropping the table.
- Deleting a period left its assertions behind, locking those dates forever
  with no UI path to clear them. Wish deletion now clears them by `wish_id`.
- `DayAssertionService` and `LeaveWishService` committed multi-statement writes
  without a transaction; a crash mid-write diverged the tables or half-deleted
  a series. Both now run in a unit of work.
- A sibling year's shortfall was never surfaced: the toast only inspected the
  edited occurrence's outcome, so a fully unfunded later year rendered as an
  empty band with no warning.
- A flexible window whose bound had entirely elapsed was dropped from the
  proposal with no outcome at all. It now reports as `unplaced`.
- Unlocking a period deleted its days instead of returning them to the planner.
- The e2e global setup posted to a route deleted in this change, which would
  have failed the whole suite before its first test.

Gates: backend 938 tests / 91% coverage, frontend 1351 / 97.4 | 92.2 | 94.37 |
97.4. Migrations 009 and 010 audited against a hand-built realistic database:
the upgrade reconciles exactly and a constraint violation fails safe, leaving
the schema at 008.

Not complete. Step 4's toggle, month picker and lock/unlock action are verified
by browser walk and unit tests, but the partial-lock readout was not exercised.
`ideas.md` §7 adds a full plan for the vacation-forfeiture defect (the planner
detects expiring days and then does nothing about them) — not implemented here.
Remaining smaller items are listed in the session's restructure notes.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T4wjgbVL4HAC5Rdaw75VbV

frontend/src/components/common/CalendarDay.test.tsx

@@ -234,7 +234,7 @@ describe('CalendarDay', () => {
     })
   })
 
-  describe('user-removed days (PlannedDayExclusion)', () => {
+  describe("user-removed days (DayAssertion, dayType: 'none')", () => {
     it('marks a removed day with its own class, a hidden badge hook and an aria descriptor', () => {
       const { getByTestId } = render(<CalendarDay date="2026-06-15" isExcluded={true} />)
       const day = getByTestId('calendar-day')

frontend/src/components/common/CalendarDay.tsx

@@ -21,10 +21,10 @@ export interface CalendarDayProps {
   isOverride?: boolean | undefined
   /** The override's value when `isOverride` is true (true = marked as a working day). */
   overrideIsWorkingDay?: boolean | null | undefined
-  /** True iff the user removed this date from the plan by hand (see
-   * `PlannedDayExclusion`). Without a mark, a day the planner deliberately
-   * skipped inside an otherwise-funded period just looks like a hole in the
-   * week. */
+  /** True iff the user removed this date from the plan by hand (a
+   * `DayAssertion` with `dayType: 'none'`, see `useDayAssertions`). Without a
+   * mark, a day the planner deliberately skipped inside an otherwise-funded
+   * period just looks like a hole in the week. */
   isExcluded?: boolean | undefined
 }
 

frontend/src/components/common/CalendarWeek.tsx

@@ -47,10 +47,10 @@ export interface CalendarWeekProps {
   onPointerEnter: (date: string) => void
   /** §3.4/§3.6 — calendar metadata (röda dagar/klämdagar/overrides) keyed by ISO date. */
   calendarDaysByDate?: Map<string, CalendarDayEntry> | undefined
-  /** Dates the user has removed from the plan by hand (see
-   * `PlannedDayExclusion`). A date the planner deliberately skipped inside an
-   * otherwise-funded period is invisible otherwise, and the hole in the week
-   * looks like a bug. */
+  /** Dates the user has removed from the plan by hand (a `DayAssertion` with
+   * `dayType: 'none'`, see `useDayAssertions`). A date the planner
+   * deliberately skipped inside an otherwise-funded period is invisible
+   * otherwise, and the hole in the week looks like a bug. */
   excludedDates?: Set<string> | undefined
   /** Opens the period editor for the clicked band's underlying period. */
   onBandClick?: ((info: BandClickInfo) => void) | undefined