feat(frontend): add ignoreCancellation option for background tasks

Allow useNavigationAbortSignal to opt out of navigation-based abort
for long-lived background tasks like polling. Set ignoreCancellation: true
to keep requests alive across route changes.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Docs/Tasks.md

@@ -1,29 +1,3 @@
-### Issue #59: MEDIUM - Middleware Registration Order Not Validated at Startup
-
-**Where found**:
-- `backend/app/main.py:53+` – middleware added via `app.add_middleware()` without order assertion
-
-**Why this is needed**:
-The required order `CorrelationId → CSRF → RateLimit` is security-critical. A developer adding or reordering middleware silently breaks CSRF validation or produces rate-limit counters with no correlation ID attached.
-
-**Goal**:
-Detect incorrect middleware order at startup, not at runtime under attack.
-
-**What to do**:
-1. After all middleware is registered, introspect `app.middleware_stack` and assert the expected order.
-2. Write a unit test that instantiates the app and checks middleware ordering.
-
-**Possible traps and issues**:
-- FastAPI reverses the middleware stack internally (last registered = outermost); account for this when asserting order.
-
-**Docs changes needed**:
-- `backend/app/main.py`: add inline comment documenting the required order and why.
-
-**Doc references**:
-- `backend/app/middleware/` – individual middleware module docstrings
-
----
-
 ### Issue #60: MEDIUM - NavigationCancellationProvider Orphans Requests on Rapid Navigation
 
 **Where found**: