refactor: separate story locales (public/) from UI locales (src/), async fetch for story messages

src/locales/ja.json

@@ -19,61 +19,5 @@
     "speed": "倍速",
     "noAutoSave": "オートセーブがありません",
     "autoSaveHint": "シーン切替時にスロット0に自動保存されます"
-  },
-  "scene": {
-    "intro": {
-      "choice": {
-        "left_door": "左にある光るドアへ向かう",
-        "right_door": "右にある普通のドアへ向かう",
-        "search": "部屋を念入りに調べる",
-        "stay": "その場に留まる"
-      }
-    },
-    "left_door": {
-      "choice": {
-        "handshake": "見知らぬ人と握手する",
-        "reject": "握手を断り、警戒を続ける"
-      }
-    },
-    "right_door": {
-      "choice": {
-        "continue": "先へ進む",
-        "back": "引き返す"
-      }
-    },
-    "trust_ending": {
-      "choice": {
-        "journey": "信頼の旅に出る（trust >= 80 が必要）",
-        "leave": "ここを去る"
-      }
-    },
-    "investigation_site": {
-      "choice": {
-        "leave": "部屋を出る"
-      }
-    },
-    "desk_detail": {
-      "choice": {
-        "return": "調査現場に戻る",
-        "leave": "立ち去る"
-      }
-    },
-    "stay": {
-      "choice": {
-        "stand": "立ち上がって去る"
-      }
-    },
-    "qte_success": {
-      "choice": {
-        "continue": "先へ進む",
-        "back": "引き返す"
-      }
-    },
-    "qte_fail": {
-      "choice": {
-        "continue": "先へ進む",
-        "back": "引き返す"
-      }
-    }
   }
-}
+}