feat(selection): expose run sector aggregates and sector filter on results API

- sector_radar: add batch sector-count aggregation and sector member lookup
  over the strict last-good membership snapshot (postgres + in-memory fakes)
- selection: add SelectionSectorReader port, list_sector_counts use case,
  and sector_stock_codes filtering via run identity resolution; queries stay
  inside the selection context per ADR 0001
- http: add GET /api/v1/selection/sectors and forward sector param on
  /results and /runs/{run_id}
- fix stale positional args in pattern-scoring run tests; cover new behavior
  with read-service, application, and HTTP contract tests

zhixing-server/tests/unit/selection/test_run.py

@@ -136,7 +136,13 @@ class FakeStore:
             kwargs["error_message"] = error_message
         self.finished = (run_id, status, kwargs)
 
-    def get_run(self, run_id: str, *, query: SelectionResultQuery | None = None):
+    def get_run(
+        self,
+        run_id: str,
+        *,
+        query: SelectionResultQuery | None = None,
+        sector_stock_codes: Sequence[str] | None = None,
+    ):
         return None
 
     def get_latest_run(
@@ -145,9 +151,16 @@ class FakeStore:
         target_trade_date: date | None = None,
         *,
         query: SelectionResultQuery | None = None,
+        sector_stock_codes: Sequence[str] | None = None,
     ):
         return None
 
+    def get_run_identity(self, run_id: str):
+        return None
+
+    def get_latest_run_identity(self, strategy: str, target_trade_date: date | None = None):
+        return None
+
 
 class BatchStore(FakeStore):
     def __init__(self) -> None:
@@ -427,8 +440,8 @@ def test_execute_loads_cases_once_and_scores_only_selected_stocks() -> None:
         reader,
         store,
         evaluator,
-        loader,
-        scorer,
+        pattern_case_loader=loader,
+        pattern_scorer=scorer,
         pattern_scoring_enabled=True,
         batch_size=1,
     )
@@ -463,8 +476,8 @@ def test_execute_isolates_pattern_scoring_failure_from_selection_status() -> Non
         BatchReader(source),
         store,
         evaluator,
-        loader,
-        scorer,
+        pattern_case_loader=loader,
+        pattern_scorer=scorer,
         pattern_scoring_enabled=True,
     )
 
@@ -497,8 +510,8 @@ def test_execute_skips_pattern_dependencies_when_feature_flag_is_disabled() -> N
         BatchReader(source),
         store,
         evaluator,
-        loader,
-        scorer,
+        pattern_case_loader=loader,
+        pattern_scorer=scorer,
         pattern_scoring_enabled=False,
     )
 
@@ -535,8 +548,8 @@ def test_execute_marks_scores_failed_when_case_library_is_unavailable() -> None:
         BatchReader(source),
         store,
         evaluator,
-        loader,
-        scorer,
+        pattern_case_loader=loader,
+        pattern_scorer=scorer,
         pattern_scoring_enabled=True,
     )