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/synthetic_rtsp.py

@@ -1,4 +1,8 @@
-"""Start/stop local fake RTSP streams (MediaMTX + ffmpeg) for dev orchestration."""
+"""Start/stop local fake RTSP streams (MediaMTX + ffmpeg) for dev orchestration.
+
+Each input file is published once (no ``-stream_loop``); when ffmpeg exits the
+process is gone — reconnect or re-orchestrate for another playthrough.
+"""
 
 from __future__ import annotations
 
@@ -203,7 +207,7 @@ class SyntheticRtspManager:
                 url_map[s.camera_id] = dest
                 pub = [
                     "ffmpeg", "-hide_banner", "-loglevel", "warning",
-                    "-re", "-stream_loop", "-1",
+                    "-re",
                     "-i", str(s.file_path),
                     "-c", "copy", "-f", "rtsp", "-rtsp_transport", "tcp", dest,
                 ]