feat(workspace): make directory paths clickable and rename "Today's Note" to "Add Memory"

Add open_workspace_directory Tauri command to open workspace/memory dirs
in the system file manager. Rename dailyMemory.createToday across all locales.

src/i18n/locales/en.json

@@ -1193,12 +1193,13 @@
     "saveSuccess": "Saved successfully",
     "saveFailed": "Failed to save",
     "loadFailed": "Failed to load",
+    "openDirectory": "Open in file manager",
     "dailyMemory": {
       "title": "Daily Memory",
       "sectionTitle": "Daily Memory",
       "cardTitle": "Daily Memory Files",
       "cardDescription": "Browse & manage daily memories",
-      "createToday": "Today's Note",
+      "createToday": "Add Memory",
       "empty": "No daily memory files yet",
       "loadFailed": "Failed to load daily memory files",
       "createFailed": "Failed to create daily memory file",

src/i18n/locales/ja.json

@@ -1193,12 +1193,13 @@
     "saveSuccess": "保存しました",
     "saveFailed": "保存に失敗しました",
     "loadFailed": "読み込みに失敗しました",
+    "openDirectory": "ファイルマネージャーで開く",
     "dailyMemory": {
       "title": "デイリーメモリー",
       "sectionTitle": "デイリーメモリー",
       "cardTitle": "デイリーメモリーファイル",
       "cardDescription": "デイリーメモリーの閲覧・管理",
-      "createToday": "今日のノート",
+      "createToday": "メモリーを追加",
       "empty": "デイリーメモリーファイルはまだありません",
       "loadFailed": "デイリーメモリーファイルの読み込みに失敗しました",
       "createFailed": "デイリーメモリーファイルの作成に失敗しました",

src/i18n/locales/zh.json

@@ -1193,12 +1193,13 @@
     "saveSuccess": "保存成功",
     "saveFailed": "保存失败",
     "loadFailed": "读取失败",
+    "openDirectory": "在文件管理器中打开",
     "dailyMemory": {
       "title": "每日记忆",
       "sectionTitle": "每日记忆",
       "cardTitle": "每日记忆文件",
       "cardDescription": "浏览管理每日记忆",
-      "createToday": "今日笔记",
+      "createToday": "添加记忆",
       "empty": "暂无每日记忆文件",
       "loadFailed": "加载每日记忆文件失败",
       "createFailed": "创建每日记忆文件失败",