fix(lab): make recorded replay seek-safe

src/k1link/web/session_api.py

@@ -48,7 +48,8 @@ from k1link.viewer.recorded import (
 from k1link.viewer.rerun_bridge import RerunSceneSettings
 
 DEFAULT_REPLAY_ACTION_ID = "stream.start-replay"
-RECORDED_MEDIA_STREAM_MANIFEST_SCHEMA = "missioncore.observation-recorded-media/v3"
+RECORDED_MEDIA_STREAM_MANIFEST_SCHEMA = "missioncore.observation-recorded-media/v4"
+RECORDED_PERCEPTION_STREAM_MANIFEST_SCHEMA = "missioncore.observation-recorded-media/v3"
 SAFE_SOURCE_ID = re.compile(r"^[A-Za-z0-9][A-Za-z0-9._:-]{0,255}$")
 SAFE_SHA256 = re.compile(r"^[a-f0-9]{64}$")
 MAX_SAFE_INTEGER = 9_007_199_254_740_991
@@ -1706,7 +1707,7 @@ def _recorded_perception_manifest_document(
     encoded_result_id = quote(video.result_id, safe="")
     base = f"/api/v1/observation-sessions/{encoded_session_id}/perception-media/{encoded_result_id}"
     return {
-        "schema_version": RECORDED_MEDIA_STREAM_MANIFEST_SCHEMA,
+        "schema_version": RECORDED_PERCEPTION_STREAM_MANIFEST_SCHEMA,
         "source_id": video.public_source_id,
         "generation_sha256": video.sha256,
         "byte_length": video.byte_length,
@@ -1795,6 +1796,13 @@ def _recorded_media_manifest_document(
                 "media_type": epoch.media_type,
                 "byte_length": epoch.init_byte_length
                 + sum(segment.byte_length for segment in epoch.segments),
+                "segment_count": len(epoch.segments),
+                "random_access_sequences": sorted(
+                    segment.sequence for segment in epoch.segments if segment.random_access
+                ),
+                "segment_end_times_seconds": [
+                    segment.end_time_seconds for segment in epoch.segments
+                ],
                 "stream_url": (
                     f"{base}/epochs/{epoch.ordinal}/recording.mp4"
                     f"?generation={manifest.generation_sha256}"