Remove obsolete schema fields and share workflow traversal

internal/store/inbox.go

@@ -469,13 +469,6 @@ func emitItem(ctx context.Context, tx *sql.Tx, emit emitFunc, kind, id, actor st
 	})
 }
 
-func formatTimePtr(t *time.Time) any {
-	if t == nil {
-		return nil
-	}
-	return formatTime(*t)
-}
-
 func parseTimePtr(s sql.NullString) (*time.Time, error) {
 	if !s.Valid {
 		return nil, nil

internal/store/migrations/079-drop-obsolete-inbox-and-session-columns.sql

@@ -0,0 +1,5 @@
+ALTER TABLE inbox_items DROP COLUMN priority;
+ALTER TABLE inbox_items DROP COLUMN blocking;
+ALTER TABLE inbox_items DROP COLUMN snoozed_until;
+ALTER TABLE inbox_responses DROP COLUMN snooze_until;
+ALTER TABLE agent_sessions DROP COLUMN workflow_stage;