test: create unresolved folder test fixtures

Add test anime folders for unresolved folder API tests.
Update test data from 'SomeFolder' to 'Unknown Anime (2020)'.
Remove stale Task 16 notes from Docs/tasks.md.

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

Docs/tasks.md

@@ -1,12 +1,3 @@
-## Task 16: Empty Schedule Days — Should reject empty schedule_days with 422
-
-**Test Result:** FAIL — `Url: http://127.0.0.1:8765/api/scheduler/config Expected status: 422 != 200`
-
-**Instructions:**
-The `Empty Schedule Days` API test sends an empty `schedule_days` value and expects a `422 Unprocessable Entity`, but the server returns `200 OK`. Review the scheduler config validation. The endpoint should reject empty schedule_days and return 422.
-
----
-
 ## Task 17: List Unresolved Folders — Should return non-empty list when folders exist
 
 **Test Result:** FAIL — `'[]' should not be empty`