feat(session-async): add /api/score/session_async with incremental session report aggregation

- New POST /api/score/session_async endpoint: same session_id calls append to one shared report
- New GET /api/score/sessions/{session_id}: returns call_count, metric_means, all job records
- New GET /api/score/session/jobs/{job_id}: individual call status
- SessionScoreJobManager: deterministic run_id from session_id, per-session mutex for CSV append, advisor regenerated on every call
- SessionScoreRequest (extends ScoreRequest + session_id), SessionScoreJobResponse, SessionStatus models added
- 24 new tests, all passing

chore(weighted-score): comment out 综合加权得分 display and computation

- report.js: hide 综合加权得分 card in report detail page
- score_jobs.js: hide 综合 chip in async job list
- report_builder.py: overall_ws=None (computation disabled)
- summary.py: weighted_score summary line disabled
- evaluator.py: weighted_score/sample_weight columns no longer written to scores.csv
- score.py /api/score: weighted_score always returns null
- score_job_manager.py + session_score_manager.py: weighted=None
- Updated 3 tests to match new behaviour (6 pre-existing failures unchanged)

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

webapp/services/report_builder.py

@@ -177,9 +177,11 @@ def build_report(run_dir: Path, metrics: list[str]) -> ReportData:
     w_means = _weighted_metric_means(score_rows_list, metrics, doc_weights)
     rounded_means = {metric: _round_or_none(value) for metric, value in w_means.items()}
 
-    overall_ws = compute_overall_weighted_score_mean(
-        score_rows_list, metric_weights, doc_weights
-    )
+    # 综合加权得分计算（已暂时禁用）
+    # overall_ws = compute_overall_weighted_score_mean(
+    #     score_rows_list, metric_weights, doc_weights
+    # )
+    overall_ws = None
 
     distributions = {
         metric: _distribution(frame, metric)