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/server.py

@@ -17,7 +17,7 @@ from fastapi.exceptions import RequestValidationError
 from fastapi.responses import FileResponse, JSONResponse
 from fastapi.staticfiles import StaticFiles
 
-from webapp.api import evaluations, llm_profiles, pipeline, runs, scenarios, score, score_jobs
+from webapp.api import evaluations, llm_profiles, pipeline, runs, scenarios, score, score_jobs, session_score_jobs
 
 STATIC_DIR = Path(__file__).resolve().parent / "static"
 logger = logging.getLogger("webapp.server")
@@ -73,6 +73,10 @@ OPENAPI_TAGS = [
             "**异步评分 API（Dify 推荐）** — `POST /api/score/async`\n\n"
             "异步方式立即返回 job_id（202），评分在后台执行，完成后自动生成完整报告（含优化建议），"
             "在「运行列表」页查看。\n\n"
+            "**Session 批量评分 API** — `POST /api/score/session_async`\n\n"
+            "适合 Dify 循环节点批量评估：同一 `session_id` 的多次调用合并为一个报告，"
+            "每次调用新增一个样本行，指标均值和优化建议增量更新。\n"
+            "通过 `GET /api/score/sessions/{session_id}` 查看 session 聚合状态。\n\n"
             "通过 `GET /api/score/jobs` 列出所有异步评分记录，"
             "`GET /api/score/jobs/{job_id}` 查询单个任务状态。\n\n"
             "**鉴权**：若 `.env` 中配置了 `SCORE_API_TOKEN`，需携带 "
@@ -111,6 +115,7 @@ def create_app() -> FastAPI:
     app.include_router(pipeline.router)
     app.include_router(score.router)
     app.include_router(score_jobs.router)
+    app.include_router(session_score_jobs.router)
 
     @app.middleware("http")
     async def access_log_middleware(request: Request, call_next):