Clarify changed and deleted files in the file viewer (#2670)

* fix(app): distinguish changed and deleted files

Successful reads now reconcile transient missing events without letting stale
cached data mask a deletion. File notices expose only actions valid for the
current buffer state.

* fix(app): preserve file state ordering

* fix(app): allow retrying file checks

* fix(app): clear unchanged file conflicts

* fix(app): keep file conflict recovery consistent

Own disk observation and read ordering in one model so stale reads and failed subscriptions cannot produce contradictory actions.

* fix(app): allow retrying file preview errors

Preserve daemon read errors and expose retry for initial and non-editable file loads.

packages/app/src/i18n/resources/ru.ts

@@ -1525,7 +1525,9 @@ export const ru: TranslationResources = {
         cursor: "Строка {{line}}, столбец {{column}}",
         preview: "Просмотр",
         source: "Исходник",
-        unavailableTitle: "Файл недоступен на диске",
+        deletedTitle: "Файл удалён с диска",
+        checkFailedTitle: "Не удалось проверить файл на диске",
+        preservedDescription: "Открытая копия сохранена.",
         conflictDescription: "Локальный буфер сохранён. Выберите версию, которую нужно оставить.",
         overwrite: "Перезаписать",
         reload: "Перезагрузить",