feat(organize/scan): transfer modes, seeding-safe relocation, inode dedup, incremental scanning

- Organizer: add move/copy/hardlink/symlink transfer modes (default move),
  per-request target_path/transfer_mode overrides, and honor organize.target_dir
  / organize.transfer_mode settings.
- keep_seeding (default on): escalate move->hardlink (cross-device->copy) so the
  qBittorrent source stays in place and continues seeding after organize.
- qBittorrent SetLocation + POST /downloads/relocate to migrate whole torrents
  while keeping them seeding.
- Scanner: FileID (device:inode) hardlink dedup to avoid duplicate recognition
  and double-counted storage; extract single-file ingest.
- Watcher: recursive watch + incremental per-file ingest/remove instead of full
  re-scan; periodic full library scan now gated behind scan.periodic_enabled
  (default off) to reduce disk wear.
- Telegram bot: handle callback_query in polling, declare allowed_updates in
  webhook, answer callbacks.
- Frontend: settings for transfer mode / keep_seeding / periodic scan; organize
  panel target dir + transfer mode overrides.
- Tests for transfer modes, organizer resolution, SetLocation, inode dedup,
  incremental ingest/remove.

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

web/src/pages/SettingsPage.tsx

@@ -158,6 +158,24 @@ const GROUPS: SettingGroup[] = [
         hint: '留空则默认整理到各媒体库对应路径（见下方参考）',
         placeholder: '/mnt/media/organized',
       },
+      {
+        key: 'organize.transfer_mode',
+        label: '默认转移方式',
+        type: 'select',
+        hint: '移动会删除源文件；复制/硬链接/软链接保留源文件，PT 做种不中断。硬链接同盘零额外占用。',
+        options: [
+          { value: 'move', label: '移动（删除源文件）' },
+          { value: 'copy', label: '复制（保留源文件）' },
+          { value: 'hardlink', label: '硬链接（保留源，做种不中断，不占双倍空间）' },
+          { value: 'symlink', label: '软链接（符号链接，保留源）' },
+        ],
+      },
+      {
+        key: 'organize.keep_seeding',
+        label: '保种（整理后继续做种上传）',
+        type: 'toggle',
+        hint: '开启后即使选择「移动」也会自动改用硬链接（跨盘退化为复制）保留源文件，确保 qBittorrent 转移后继续做种上传。',
+      },
       {
         key: 'organize.movie_format',
         label: '电影命名格式',
@@ -195,6 +213,12 @@ const GROUPS: SettingGroup[] = [
         type: 'text',
         placeholder: 'zh-CN',
       },
+      {
+        key: 'scan.periodic_enabled',
+        label: '周期性整库重扫',
+        type: 'toggle',
+        hint: '默认关闭。文件新增/变更由实时监听增量入库，无需定时全量重扫。开启会每 60 分钟重扫整库，频繁读盘会损伤硬盘，一般无需开启。',
+      },
     ],
   },
   {