🚀 feat: add enabled/disabled channel filtering & optimize type-based pagination (#1289)

WHAT’S NEW
• Backend
  – Introduced `parseStatusFilter` helper to normalize `status` query across handlers.
  – `GET /api/channel` & `GET /api/channel/search` now accept `status=enabled|disabled` to return only enabled or disabled channels.
  – Tag-mode branch respects both `statusFilter` and `typeFilter`; SQL paths trimmed to one query + one lightweight `GROUP BY` for `type_counts`.

• Frontend (`ChannelsTable.js`)
  – Added “Status Filter” `<Select>` (All / Enabled / Disabled) with localStorage persistence.
  – All data-loading and search requests now always append `type` (when not “all”) and `status` params, so filtering & pagination are handled entirely server-side.
  – Removed client-side post-filtering for type, preventing short pages and reducing CPU work.
  – Tabs’ type counts stay in sync via backend-provided `type_counts`.

IMPROVEMENTS
• Eliminated duplicated status-parsing logic; single source of truth eases future extension.
• Reduced redundant queries, improved consistency of counts in UI.
• Secured key leakage with `Omit("key")` unchanged; no perf regressions observed.

Closes #1289

web/src/i18n/locales/en.json

@@ -1732,5 +1732,6 @@
   "确认冲突项修改": "Confirm conflict item modification",
   "该模型存在固定价格与倍率计费方式冲突，请确认选择": "The model has a fixed price and ratio billing method conflict, please confirm the selection",
   "当前计费": "Current billing",
-  "修改为": "Modify to"
+  "修改为": "Modify to",
+  "状态筛选": "Status filter"
 }