## Fix Task 7 — Build-breaking issues in RoomsPage

### Changes made to `apps/admin/src/pages/Rooms/index.tsx`

1. **Restored `const RoomsPage: React.FC = () => {` wrapper** — was accidentally removed, leaving state hooks dangling at module scope. Added at line 66.

2. **Restored `const [data, setData] = useState<any[]>([]);`** — was removed but referenced by `buildings` useMemo and `fetchData`. Added right after the component opener.

3. **Added `useCallback` to React import** (line 1) — needed for wrapping fetchBeds/fetchLockers.

4. **Fixed `handleSave` function** — its closing `};` was accidentally overwritten by the fetchBeds edit. Restored at line 160.

5. **Wrapped `fetchBeds` and `fetchLockers` in `useCallback`** — they're in the `columns` useMemo deps array, but as plain `const` functions they'd be recreated every render, causing unnecessary re-renders. Now wrapped with `[]` deps since they only reference stable `api` and state setters.

6. **Deleted orphaned leftover code** — old `} catch (e) { console.error(e); }\n  };` from the pre-useCallback fetchBeds definition was still present after the replacement.

7. **Fixed broken action column JSX** — the ternary for archived/non-archived rows had mixed branches: the archived=true branch contained ALL buttons (恢复, 查看, 编辑, 归档) instead of only 恢复, with a dangling `</>` closing a non-existent fragment. Restructured to: archived branch → just `<Popconfirm>恢复</Popconfirm>`; else branch → fragment-wrapped `<查看/编辑/归档>`. Also fixed missing `]: [deps]` useMemo closing after the action column array member.

8. **Removed Tooltip** — not imported/unused. (Already clean; no action needed.)

### Verification
- `npx tsc --noEmit` passes with zero errors.