feat: #1 telemetry record/playback with auto-race detection

- TelemetryRecorder: manual + auto mode (IsRaceOn edge detection)
- TelemetryPlayer: timed packet replay into _handle_packet pipeline
- .tsr format: [uint32 elapsed_ms][uint32 len][bytes]
- Settings UI: start/stop, auto toggle, recording list, play button
- API: /record/*, /playback/*, /recordings

server/api.py

@@ -422,3 +422,50 @@ async def api_update_forward_targets(data: dict[str, Any]):
     save_config(cfg)
     telemetry_listener.forwarder.reload_targets()
     return {"ok": True, "active": telemetry_listener.forwarder.active}
+
+
+# ---- Record & Playback ----
+from server.recorder import TelemetryRecorder, TelemetryPlayer
+
+_recorder = None
+_player = None
+
+def _get_recorder():
+    global _recorder
+    if _recorder is None: _recorder = TelemetryRecorder(telemetry_listener)
+    return _recorder
+
+def _get_player():
+    global _player
+    if _player is None: _player = TelemetryPlayer(telemetry_listener)
+    return _player
+
+@router.post("/record/start")
+async def api_start_record():
+    _get_recorder().start()
+    return {"ok": True, "recording": True}
+
+@router.post("/record/stop")
+async def api_stop_record():
+    _get_recorder().stop()
+    return {"ok": True, "recording": False}
+
+@router.get("/record/status")
+async def api_record_status():
+    return {"recording": _get_recorder().is_recording, "playing": _get_player().is_playing}
+
+@router.get("/recordings")
+async def api_list_recordings():
+    return TelemetryPlayer.list_recordings()
+
+@router.post("/playback/start")
+async def api_start_playback(data: dict):
+    filename = data.get("filename", "")
+    if not filename: raise HTTPException(400, "filename required")
+    _get_player().start(filename)
+    return {"ok": True, "playing": True}
+
+@router.post("/playback/stop")
+async def api_stop_playback():
+    _get_player().stop()
+    return {"ok": True, "playing": False}

server/recorder.py

@@ -0,0 +1,134 @@
+from __future__ import annotations
+
+import asyncio
+import os
+import struct
+import time
+from pathlib import Path
+
+from utils.logger import get_logger
+
+logger = get_logger(__name__)
+
+RECORDINGS_DIR = Path(__file__).resolve().parent.parent / "data" / "recordings"
+RECORDINGS_DIR.mkdir(parents=True, exist_ok=True)
+
+
+class TelemetryRecorder:
+    def __init__(self, listener):
+        self._listener = listener
+        self._file = None
+        self._recording = False
+        self._auto_mode = False
+        self._start_time = 0.0
+        self._last_race_on = False
+
+    @property
+    def is_recording(self) -> bool:
+        return self._recording
+
+    @property
+    def current_file(self) -> str | None:
+        return str(self._file.name) if self._file else None
+
+    def start(self):
+        if self._recording:
+            return
+        ts = time.strftime("%Y%m%d_%H%M%S")
+        self._file = open(RECORDINGS_DIR / f"rec_{ts}.tsr", "wb")
+        self._recording = True
+        self._start_time = time.time()
+        logger.info("Recording started: %s", self._file.name)
+
+    def stop(self):
+        if not self._recording:
+            return
+        self._recording = False
+        if self._file:
+            self._file.close()
+            self._file = None
+        logger.info("Recording stopped")
+
+    def set_auto(self, enabled: bool):
+        self._auto_mode = enabled
+        self._last_race_on = False
+        if not enabled:
+            self.stop()
+
+    def write_packet(self, data: bytes):
+        if self._auto_mode:
+            try:
+                is_race = struct.unpack_from("<i", data, 0)[0] == 1
+            except Exception:
+                is_race = True
+
+            if is_race and not self._last_race_on:
+                self.start()
+            elif not is_race and self._last_race_on and self._recording:
+                self.stop()
+            self._last_race_on = is_race
+
+        if not self._recording or not self._file:
+            return
+        elapsed_ms = int((time.time() - self._start_time) * 1000)
+        self._file.write(struct.pack("<II", elapsed_ms, len(data)))
+        self._file.write(data)
+
+
+class TelemetryPlayer:
+    def __init__(self, listener):
+        self._listener = listener
+        self._task: asyncio.Task | None = None
+        self._playing = False
+
+    @property
+    def is_playing(self) -> bool:
+        return self._playing
+
+    def start(self, filename: str):
+        if self._playing:
+            return
+        path = RECORDINGS_DIR / filename
+        if not path.exists():
+            logger.error("Recording not found: %s", filename)
+            return
+        loop = asyncio.get_event_loop()
+        self._task = loop.create_task(self._play_loop(path))
+        self._playing = True
+        logger.info("Playback started: %s", filename)
+
+    def stop(self):
+        self._playing = False
+        if self._task and not self._task.done():
+            self._task.cancel()
+            self._task = None
+        logger.info("Playback stopped")
+
+    async def _play_loop(self, path: Path):
+        try:
+            data = path.read_bytes()
+            offset = 0
+            play_start = time.time()
+            while offset < len(data) and self._playing:
+                elapsed_ms, length = struct.unpack_from("<II", data, offset)
+                offset += 8
+                packet = data[offset:offset + length]
+                offset += length
+
+                target_time = play_start + elapsed_ms / 1000.0
+                delay = target_time - time.time()
+                if delay > 0:
+                    await asyncio.sleep(min(delay, 0.5))
+
+                self._listener._handle_packet(packet, ("127.0.0.1", 0))
+        except asyncio.CancelledError:
+            pass
+        except Exception as e:
+            logger.error("Playback error: %s", e)
+        finally:
+            self._playing = False
+
+    @staticmethod
+    def list_recordings() -> list[dict]:
+        return [{"name": f.name, "size": f.stat().st_size, "time": f.stat().st_mtime}
+                for f in sorted(RECORDINGS_DIR.glob("*.tsr"), key=lambda x: x.stat().st_mtime, reverse=True)]

server/telemetry/listener.py

@@ -151,6 +151,10 @@ class TelemetryListener:
 
         self.forwarder.forward(data)
 
+        from server.api import _recorder
+        if _recorder and _recorder.is_recording:
+            _recorder.write_packet(data)
+
         td = None
         if self._parser:
             td = self._parser.parse(data, addr)