feat: consumption log top1 + elapsed since recording; RTSP play once

- Add top1_name/top1_conf to TSV and show top1–3 in pending markdown
- Add 相对开录 column and pass since_recording_start from surgery start
- Track surgery_started_wall and format_elapsed_mmss_since in session registry
- Remove ffmpeg stream_loop from synthetic/demo fake RTSP (play once)
- Fix fake_rtsp_from_file poll loop indentation; update README
- Extend consumption TSV tests; add face test PNGs under tests/faces

Made-with: Cursor

app/services/video/session_manager.py

@@ -30,6 +30,7 @@ from app.services.video.session_registry import (
     RunningSurgery,
     SurgerySessionRegistry,
     SurgerySessionState,
+    format_elapsed_mmss_since,
 )
 from app.services.tear_gated_segment_consumption.product_map import (
     load_tear_segment_name_to_id,
@@ -166,6 +167,7 @@ class CameraSessionManager:
         state = SurgerySessionState(
             candidate_consumables=list(resolved),
             name_to_code=name_to_code,
+            surgery_started_wall=time.time(),
         )
         stop_event = asyncio.Event()
         readies = [asyncio.Event() for _ in camera_ids]
@@ -447,9 +449,13 @@ class CameraSessionManager:
 
                     if bp.VIDEO_LOG_INFERENCE_RESULTS:
                         logger.info(
-                            "Vision result surgery={} camera={} top1={}({:.3f}) top2={}({:.3f}) top3={}({:.3f})",
+                            "Vision result surgery={} camera={} 相对开录={} top1={}({:.3f}) top2={}({:.3f}) top3={}({:.3f})",
                             surgery_id,
                             camera_id,
+                            format_elapsed_mmss_since(
+                                state.surgery_started_wall,
+                                at_epoch=time.time(),
+                            ),
                             snap.t1_name,
                             snap.t1_conf,
                             snap.t2_name,