feat(workspace): add full-text search for daily memory files

Add backend search command that performs case-insensitive matching
across all daily memory files, supporting both date and content queries.
Frontend includes animated search bar (⌘F), debounced input, snippet
display with match count badge, and search state preservation across
edits.

src/i18n/locales/en.json

@@ -1205,7 +1205,14 @@
       "deleteSuccess": "Daily memory file deleted",
       "deleteFailed": "Failed to delete daily memory file",
       "confirmDeleteTitle": "Delete Daily Memory",
-      "confirmDeleteMessage": "Delete the daily memory for {{date}}? This cannot be undone."
+      "confirmDeleteMessage": "Delete the daily memory for {{date}}? This cannot be undone.",
+      "searchPlaceholder": "Search full content...",
+      "searchScopeHint": "Full-text search across all daily memories. ⌘F",
+      "searchCloseHint": "Esc to close",
+      "noSearchResults": "No daily memories match your search.",
+      "searching": "Searching...",
+      "searchFailed": "Search failed",
+      "matchCount": "{{count}} match(es)"
     }
   },
   "openclaw": {

src/i18n/locales/ja.json

@@ -1205,7 +1205,14 @@
       "deleteSuccess": "デイリーメモリーファイルを削除しました",
       "deleteFailed": "デイリーメモリーファイルの削除に失敗しました",
       "confirmDeleteTitle": "デイリーメモリーを削除",
-      "confirmDeleteMessage": "{{date}} のデイリーメモリーを削除しますか？この操作は取り消せません。"
+      "confirmDeleteMessage": "{{date}} のデイリーメモリーを削除しますか？この操作は取り消せません。",
+      "searchPlaceholder": "全文検索...",
+      "searchScopeHint": "すべてのデイリーメモリーを全文検索 ⌘F",
+      "searchCloseHint": "Escで閉じる",
+      "noSearchResults": "検索に一致するデイリーメモリーはありません。",
+      "searching": "検索中...",
+      "searchFailed": "検索に失敗しました",
+      "matchCount": "{{count}}件一致"
     }
   },
   "openclaw": {

src/i18n/locales/zh.json

@@ -1205,7 +1205,14 @@
       "deleteSuccess": "每日记忆文件已删除",
       "deleteFailed": "删除每日记忆文件失败",
       "confirmDeleteTitle": "删除每日记忆",
-      "confirmDeleteMessage": "确定删除 {{date}} 的每日记忆吗？此操作不可撤销。"
+      "confirmDeleteMessage": "确定删除 {{date}} 的每日记忆吗？此操作不可撤销。",
+      "searchPlaceholder": "搜索全文内容...",
+      "searchScopeHint": "全文搜索所有每日记忆 ⌘F",
+      "searchCloseHint": "Esc 关闭",
+      "noSearchResults": "没有找到匹配的每日记忆。",
+      "searching": "搜索中...",
+      "searchFailed": "搜索失败",
+      "matchCount": "{{count}} 处匹配"
     }
   },
   "openclaw": {