v1.6.5: fix attendance unique constraint, schema sync, seed script

- Change attendance idx_attendance_user_date from unique to index (allow multiple shifts per day)
- Reset migrations to single baseline init migration
- Add seed script with admin user (admin/admin)
- Update CLAUDE.md with migration workflow documentation
- Various frontend fixes (queries, pages, hooks)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/routes/admin/profile.ts

@@ -36,6 +36,13 @@ export default async function profileRoutes(
     const body = parsed.data;
     const userId = request.authData!.userId;
 
+    if (body.new_password && !body.current_password) {
+      return error(reply, "Pro změnu hesla zadejte aktuální heslo", 400);
+    }
+    if (body.current_password && !body.new_password) {
+      return error(reply, "Pro změnu hesla zadejte nové heslo", 400);
+    }
+
     const data: Record<string, unknown> = {};
     if (body.email) {
       data.email = String(body.email).trim();