feat(calendar): show regional holidays and observances

public/locales/zh-TW.json

@@ -367,7 +367,47 @@
     "emptyDay": "這一天還沒有記憶或目標節點。",
     "openToday": "寫下一段記憶",
     "writeMemory": "新增記憶",
-    "openTasks": "開啟待辦"
+    "openTasks": "開啟待辦",
+    "holidayCountry": "國家或地區",
+    "autoCountry": "自動（{country}）",
+    "publicHoliday": "國定假日",
+    "festival": "節日",
+    "workingDay": "工作日",
+    "observed": "補假",
+    "estimated": "日期待確認",
+    "workingWeekend": "週末補班",
+    "loadingHolidays": "正在載入節假日…",
+    "holidayUnavailable": "節假日資料暫時無法取得。",
+    "retryHolidays": "重試",
+    "holidaySource": "國定假日資料",
+    "outsideRange": "節假日資料涵蓋 2024—2030 年。",
+    "festivals": {
+      "valentine": "情人節",
+      "earth": "世界地球日",
+      "halloween": "萬聖節",
+      "christmasEve": "平安夜",
+      "teachers": "教師節"
+    },
+    "holidayNames": {
+      "New Year's Day": "元旦",
+      "Chinese New Year (Spring Festival)": "春節",
+      "Chinese New Year": "春節",
+      "Chinese New Year's Eve": "除夕",
+      "Tomb-Sweeping Day": "清明節",
+      "Labor Day": "勞動節",
+      "Dragon Boat Festival": "端午節",
+      "Mid-Autumn Festival": "中秋節",
+      "National Day": "國慶日",
+      "Christmas Day": "聖誕節",
+      "Christmas Eve": "平安夜",
+      "Good Friday": "耶穌受難日",
+      "Easter Monday": "復活節星期一",
+      "Peace Memorial Day": "和平紀念日",
+      "Children's Day": "兒童節",
+      "Constitution Day": "行憲紀念日",
+      "Confucius' Birthday": "孔子誕辰"
+    },
+    "holidayCaveat": "日期可能調整，請以當地官方公告為準。"
   },
   "tasks": {
     "eyebrow": "目標與待辦",