fix(types): resolve pre-existing basedpyright errors in tests

Fix ~790 basedpyright errors across the test suite:
- Type stub subclasses of real production classes with super().__init__()
- Add missing generic type arguments and Dict[str, Any] annotations
- Add None guards before subscript/member access
- Adapt tests to production API changes (removed dead handlers,
  PersistentModelCache.get_default, _i18n_filter_added location)

tests/metadata_ops/test_metadata_ops.py

@@ -9,6 +9,7 @@ Mock targets must match where imports are resolved inside each function
 
 from __future__ import annotations
 
+from typing import Any
 from unittest import mock
 
 import pytest
@@ -28,14 +29,14 @@ from py.metadata_ops import (
 
 
 class MockCache:
-    def __init__(self, raw_data: list[dict] | None = None):
+    def __init__(self, raw_data: list[dict[str, Any]] | None = None):
         self.raw_data = raw_data or []
 
 
 class MockScanner:
     """Simulates a ModelScanner for testing."""
 
-    def __init__(self, raw_data: list[dict] | None = None):
+    def __init__(self, raw_data: list[dict[str, Any]] | None = None):
         self._raw_data = raw_data or []
         self.update_single_model_cache = mock.AsyncMock(return_value=True)
 
@@ -599,7 +600,7 @@ class TestExtractGalleryTableImages:
 """
 
     @staticmethod
-    def _extract(md: str, repo: str = _REPO, existing: set | None = None):
+    def _extract(md: str, repo: str = _REPO, existing: set[str] | None = None):
         from py.services.agent.skills.enrich_hf_metadata.readme_processor import \
             extract_gallery_table_images
         return extract_gallery_table_images(md, repo, existing_urls=existing)
@@ -643,7 +644,7 @@ class TestExtractGalleryTableImages:
 class TestCleanReadmeForLlm:
 
     @staticmethod
-    def _clean(md: str, max_length: int = 6000) -> str:
+    def _clean(md: str | None, max_length: int = 6000) -> str:
         from py.services.agent.skills.enrich_hf_metadata.readme_processor import \
             clean_readme_for_llm
         return clean_readme_for_llm(md, max_length=max_length)
@@ -651,7 +652,7 @@ class TestCleanReadmeForLlm:
     # -- basic guards --------------------------------------------------------
 
     def test_none_returns_empty(self):
-        assert self._clean(None) == ""  # type: ignore[arg-type]
+        assert self._clean(None) == ""
 
     def test_empty_returns_empty(self):
         assert self._clean("") == ""

tests/metadata_ops/test_readme_processor.py

@@ -19,6 +19,8 @@ _MODULE_PATH = Path(__file__).parents[2] / "py" / "services" / "agent" / "skills
 def R():
     """Load the ``readme_processor`` module once per session."""
     spec = importlib.util.spec_from_file_location("readme_processor", str(_MODULE_PATH))
+    assert spec is not None
+    assert spec.loader is not None
     mod = importlib.util.module_from_spec(spec)
     spec.loader.exec_module(mod)
     return mod