feat(core): support tag search for ai chat (#10965)

Close [BS-2785](https://linear.app/affine-design/issue/BS-2785).
Close [BS-2786](https://linear.app/affine-design/issue/BS-2786).

![截屏2025-03-18 21.22.34.png](https://graphite-user-uploaded-assets-prod.s3.amazonaws.com/sJGviKxfE3Ap685cl5bj/fae7216a-0402-4f14-a63c-b89f5223fc72.png)

packages/frontend/i18n/src/i18n.gen.ts

@@ -6829,6 +6829,10 @@ export function useAFFiNEI18N(): {
       * `Recent`
       */
     ["com.affine.editor.at-menu.recent-docs"](): string;
+    /**
+      * `Tags`
+      */
+    ["com.affine.editor.at-menu.tags"](): string;
     /**
       * `Loading...`
       */

packages/frontend/i18n/src/resources/en.json

@@ -1697,6 +1697,7 @@
   "com.affine.editor.journal-conflict.title": "Duplicate Entries in Today's Journal",
   "com.affine.editor.at-menu.link-to-doc": "Search for \"{{query}}\"",
   "com.affine.editor.at-menu.recent-docs": "Recent",
+  "com.affine.editor.at-menu.tags": "Tags",
   "com.affine.editor.at-menu.loading": "Loading...",
   "com.affine.editor.at-menu.new-doc": "New",
   "com.affine.editor.at-menu.create-page": "New \"{{name}}\" page",