feat(db): add sqlx migrate feature and renumber migration files

- Add 'migrate' feature to sqlx dependency
- Renumber migrations to fix duplicate version numbers (two 014 files)
- Re-sequence migrations 009-012 for continuous ordering
- Add ALTER TABLE ADD COLUMN IF NOT EXISTS baseline for notification
  table to handle existing databases missing newer columns
- Remove deleted IM migration files (009-012) that were superseded

migrate/001_init.sql

@@ -1905,6 +1905,17 @@ CREATE TABLE IF NOT EXISTS notification (
     deleted_at TIMESTAMPTZ NULL
 
 );
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS repo_id UUID NULL REFERENCES repo(id) ON DELETE CASCADE;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS issue_id UUID NULL REFERENCES issue(id) ON DELETE CASCADE;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS pull_request_id UUID NULL REFERENCES pull_request(id) ON DELETE CASCADE;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS channel_id UUID NULL REFERENCES channel(id) ON DELETE CASCADE;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS message_id UUID NULL REFERENCES message(id) ON DELETE CASCADE;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS target_type TEXT NULL;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS target_id UUID NULL;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS action_url TEXT NULL;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS priority TEXT NOT NULL DEFAULT 'normal';
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS metadata JSONB NULL;
+ALTER TABLE notification ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ NULL;
 CREATE INDEX IF NOT EXISTS idx_notification_user_id ON notification (user_id);
 CREATE INDEX IF NOT EXISTS idx_notification_actor_id ON notification (actor_id);
 CREATE INDEX IF NOT EXISTS idx_notification_workspace_id ON notification (workspace_id);