TaskEntity.Number is a global, monotonically increasing, never-reused
integer (displayed as #123), allocated from AppSettingsEntity.NextTaskNumber
via a single UPDATE...RETURNING statement rather than MAX(number)+1, which
would reissue a deleted task's number. Both insert paths (TaskRepository.
AddAsync and CreateChildAsync) route through the new TaskNumberAllocator,
with a bounded retry on a unique-index collision. One migration adds the
columns, backfills existing rows in creation order, and creates the unique
index afterwards. Data-layer only; MCP/UI wiring is later slices.
Adds a user/MCP-declared task dependency (DependsOnTaskId) distinct from the
planning chain's internal BlockedByTaskId: add_task/update_task can set it,
the queue picker skips a Queued task until the dependency reaches Done, a
Failed/Cancelled dependency leaves the dependent blocked instead of starving
silently, and setting a link rejects self-reference/unknown-id/cycles.
get_task/list_tasks/batch_get_tasks now report blocked/blockedReason, and
wait_for_task_change reports "Blocked" immediately instead of running out its
timeout on a task the picker will never claim.
preview_merge/preview_merge_set gain staleFiles: files a branch touches that
the target branch also changed since the branch's fork point, a more honest
staleness signal than `behind` alone.
- Add SqliteForeignKeyInterceptor (DbConnectionInterceptor) registered via
OnConfiguring so every IDbContextFactory-created context runs
PRAGMA foreign_keys=ON, not only the MigrateAndConfigure context.
- DefaultListsSeeder: replace TOCTOU read-then-insert with atomic
INSERT … SELECT … WHERE NOT EXISTS — one SQLite writer lock, no race.
- AppSettingsRepository.GetAsync: catch DbUpdateException on the
get-or-create path and re-read so concurrent startup cannot throw.
- Migration 20260609000000_UniqueListName: de-duplicates empty list rows
(startup-race leftovers) then adds a UNIQUE index on lists.name.
- ForeignKeyTests: verifies ON DELETE SET NULL (blocked_by_task_id) is
enforced on a fresh DbContext with no manual PRAGMA call.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>