Merge origin/dev (Feature 20 scheduler) into Feature 21 Home dashboard

Keep both the scheduler registrations and the Home service wiring in
cmd/server, pass the scheduler wake function to plan.NewService in the
Home and server tests, and document that boot catch-up processes every
unclaimed fire time within 24 hours, oldest first (F20-02).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

migrations/queries/schedule_runs.sql

@@ -0,0 +1,6 @@
+-- name: ClaimScheduleRun :execrows
+-- Claims one period of a schedule. The insert is the claim: 1 row means
+-- this caller owns the period, 0 rows means it was already claimed.
+INSERT INTO schedule_runs (id, schedule, period_key, created_at)
+VALUES (?, ?, ?, ?)
+ON CONFLICT (schedule, period_key) DO NOTHING;