feat(hosts): add drag-and-drop and global subscription ordering (#6895)

Hosts already had one saved order on the Hosts page, but subscriptions honoured
it only inside each inbound, so a host of a later inbound could never come before
one of an earlier inbound (#6894). A new opt-in setting makes raw/base64,
Clash/Mihomo and JSON subscriptions follow the Hosts page order across inbounds;
the default keeps today's inbound-first output unchanged. The Hosts table gains
drag-and-drop reordering next to the Up/Down buttons, on a pointer-reorder hook
the Routing Rules table now shares.

frontend/src/pages/api-docs/endpoints.ts

@@ -1893,7 +1893,8 @@ export const sections: readonly Section[] = [
       {
         method: 'POST',
         path: '/panel/api/hosts/reorder',
-        summary: 'Set host group sort order by the position of each groupId in the array.',
+        summary:
+          'Set host group sort order by the position of each groupId in the array. IDs must be unique and refer to existing groups; omitted groups follow in their previous order.',
         body: '{\n  "ids": ["abc-123", "def-456"]\n}',
       },
       {