[chore] remove all remaining type:ignore suppressions from tests/

Converts 115 `# type: ignore[...]` suppressions across 23 test files to
no-suppression patterns (helper-return widening to Any, local Any aliases,
cc:Any aliases, cast at narrow call sites, typed fixtures) so the hard
no-type:ignore convention holds across tests/. No test logic or assertions
changed — only mock-wiring mechanics and type annotations.

Gate: ruff check tests/ clean; mypy tests/ (538 files) clean; 176 changed-file
tests pass. Zero real suppressions remain (the 7 grep hits are 3 hygiene-
checker string-literal test inputs and 4 prose mentions in comments).

tests/integration/services/test_dep_update_probe.py

@@ -8,7 +8,7 @@ or committing/pushing. Fail-safe: a null/failing command returns False.
 from __future__ import annotations
 
 import subprocess
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Any
 from unittest.mock import AsyncMock, MagicMock
 
 import pytest
@@ -36,9 +36,9 @@ def _make_read_clone(tmp_path: Path) -> Path:
     return repo
 
 
-def _svc(read_clone: Path) -> WorkspaceService:
-    svc = WorkspaceService.__new__(WorkspaceService)
-    svc.ensure_read_clone = AsyncMock(return_value=read_clone)  # type: ignore[method-assign]
+def _svc(read_clone: Path) -> Any:
+    svc: Any = WorkspaceService.__new__(WorkspaceService)
+    svc.ensure_read_clone = AsyncMock(return_value=read_clone)
     return svc