fix(migrations): add schema_version inserts to migrations 022-027

Defense-in-depth: The migration framework already handles missing
inserts via INSERT OR REPLACE (db.rs:174), but adding explicit
inserts to .sql files ensures consistency and makes migrations
self-documenting.

Migrations affected:
- 022_notes_query_index
- 024_note_documents  
- 025_note_dirty_backfill
- 026_scoring_indexes
- 027_surgical_sync_runs

migrations/022_notes_query_index.sql

@@ -19,3 +19,6 @@ CREATE INDEX IF NOT EXISTS idx_discussions_mr_id ON discussions(merge_request_id
 -- Immutable author identity column (GitLab numeric user ID)
 ALTER TABLE notes ADD COLUMN author_id INTEGER;
 CREATE INDEX IF NOT EXISTS idx_notes_author_id ON notes(author_id) WHERE author_id IS NOT NULL;
+
+INSERT INTO schema_version (version, applied_at, description)
+VALUES (22, strftime('%s', 'now') * 1000, '022_notes_query_index');