feat(wallets): fixed max-height list + manage scanned folders

Two wallets-modal changes:

- The wallet list now always renders at its max height (kMaxVisibleRows) instead
  of shrinking to the wallet count, so the modal is a consistent size whether you
  have one wallet or many — fewer rows leave empty space, more than 7 scroll.

- Add a "Scanned folders" manager: each user-added scan folder is listed with a
  control to stop scanning it (removeExtraFolder + save + re-scan so its wallets
  drop out). Paths front-elide to keep the identifying leaf visible, with a
  full-path tooltip. The card-height math reserves the manager's rows so nothing
  clips. Two new i18n keys (wallets_scanned_folders / wallets_remove_folder),
  translated across all 8 languages; CJK subset rebuilt.

Verified on the sweep at 1.0 and 1.5x DPI: max-height list on both the few- and
many-wallet surfaces, the folder manager renders and stays clear of the footer.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

res/lang/ko.json

@@ -1356,7 +1356,9 @@
     "wallets_open_failed": "이 지갑을 제자리에서 열 수 없습니다. 데이터 디렉터리와 다른 드라이브에 있을 가능성이 높습니다 — 같은 드라이브로 옮기세요 (Windows에서는 개발자 모드를 켜면 드라이브 간 링크도 가능합니다).",
     "wallets_open_folder": "폴더 위치 열기",
     "wallets_open_inplace_tt": "이 지갑을 있는 자리에서 엽니다 — 데이터 디렉터리에 링크 (복사 없음)",
+    "wallets_remove_folder": "이 폴더 스캔 중지",
     "wallets_reveal": "폴더 열기",
+    "wallets_scanned_folders": "스캔한 폴더:",
     "wallets_sort_addresses": "주소",
     "wallets_sort_asc": "오름차순 (오래된/적은/작은 순)",
     "wallets_sort_by": "정렬:",