fix(i18n): overhaul Japanese translations, localise pending UI labels, and update documentation

- Overhaul Japanese translation catalogue and synchronize with current documentation
- Localise pending UI labels across dialogues, panels, and settings
- Add Japanese translation mapping for provisional LiveSync messages
- Update and refine all Japanese documentation files
- Strip weak ETag prefix in ObsHttpHandler for object storage compatibility

src/serviceFeatures/redFlag.simpleFetch.ts

@@ -77,7 +77,9 @@ async function confirmTranslatedChoice(
     const selected = await host.services.UI.confirm.confirmWithMessage(title, message, labels, $msg(defaultAction), 0);
     if (selected === false) return false;
     const index = labels.indexOf(selected);
-    return index < 0 ? false : buttons[index];
+    if (index >= 0) return buttons[index];
+    const buttonIndex = buttons.indexOf(selected as AllMessageKeys);
+    return buttonIndex < 0 ? false : buttons[buttonIndex];
 }
 
 export async function askSimpleFetchMode(

src/serviceFeatures/redFlag.simpleFetch.unit.spec.ts

@@ -220,7 +220,7 @@ describe("Fetch restart confirmation regressions", () => {
         expect(confirmWithMessage).toHaveBeenCalledOnce();
         expect(confirmWithMessage.mock.calls[0][1]).toContain("example.invalid");
         expect(confirmWithMessage.mock.calls[0][1]).toContain(REMOTE_WINS);
-        expect(confirmWithMessage.mock.calls[0][1]).toContain(KEEP_LOCAL);
+        expect(confirmWithMessage.mock.calls[0][1]).toContain($msg(KEEP_LOCAL));
         expect(files.get(flagPath)).toBe(rememberedMarkdown);
     });
 

src/serviceFeatures/redFlag.unit.spec.ts

@@ -497,8 +497,7 @@ describe("Red Flag Feature", () => {
             expect(host.mocks.rebuilder.$fetchLocalDBFast).toHaveBeenCalled();
             expect(synchroniseAllFilesBetweenDBandStorage).toHaveBeenCalled();
             const firstPrompt = host.mocks.ui.confirm.confirmWithMessage.mock.calls[0]?.[1];
-            expect(firstPrompt).toContain("data retrieved from this remote source");
-            expect(firstPrompt).not.toContain("remote server");
+            expect(firstPrompt).toContain("We are about to retrieve the remote data.");
             // We can't easily check performFullScan call here because it's imported,
             // but we can verify rebuilder was called.
         });