feat: deliver offline issue captures after app close (#250)

Closes #250

src/main.py

@@ -426,7 +426,7 @@ app.include_router(frontend_router)
 @app.middleware("http")
 async def prevent_live_api_caching(request, call_next):
     response = await call_next(request)
-    if request.url.path in {"/api/v1/context", "/api/v1/events", "/api/v1/live", "/api/v1/available-issues", "/api/v1/search", "/api/v1/work-route"} or request.url.path.startswith("/api/v1/work/") or (
+    if request.url.path in {"/api/v1/context", "/api/v1/background-identity", "/api/v1/events", "/api/v1/live", "/api/v1/available-issues", "/api/v1/search", "/api/v1/work-route"} or request.url.path.startswith("/api/v1/work/") or (
         request.url.path.startswith("/api/v1/repos/")
         and request.url.path.endswith("/review")
     ) or request.url.path.startswith("/api/v1/notifications") or (
@@ -533,6 +533,23 @@ async def context() -> JSONResponse:
     return JSONResponse(_context_payload(user_data, repo_data, issues_data, prs_data))
 
 
+@app.get("/api/v1/background-identity")
+async def background_identity() -> JSONResponse:
+    """Return only the account key required to safely drain a browser outbox."""
+    try:
+        user = await current_user()
+        login = user.get("login") if isinstance(user, dict) else None
+        if not isinstance(login, str) or not login.strip():
+            raise ValueError("Gitea user response did not include a login")
+    except Exception:
+        return JSONResponse(
+            {"error": "Gitea identity is temporarily unavailable"},
+            status_code=503,
+            headers={"Retry-After": "1"},
+        )
+    return JSONResponse({"login": login})
+
+
 @app.get("/api/v1/search")
 async def global_search(
     q: str = Query(min_length=2, max_length=100),