feat(planning): consolidate recorded-route localization and spatial scene

Preserve the completed teach-and-repeat laboratory stage: reference preparation, cascaded acquisition, local tracking and recovery, recording lifecycle, replay qualification, and persistent Rerun scene controls. Document the open grid-picking regression and Rerun upgrade contract. No autonomous driving or loop-closure optimization is claimed.

apps/control-station/src/components/MseFmp4WebSocketPlayer.tsx

@@ -28,6 +28,7 @@ export interface CameraLeaseRetryBudget {
 const CAMERA_LEASE_RETRY_DELAYS = [400, 1_000, 2_000, 5_000] as const;
 export const CAMERA_FIRST_MEDIA_TIMEOUT_MS = 8_000;
 export const CAMERA_FIRST_PLAYABLE_FRAME_TIMEOUT_MS = 8_000;
+export const CAMERA_BUFFERING_NOTICE_DELAY_MS = 1_000;
 // The gateway may release an 8 MiB / 64-fragment slow-reader backlog after a
 // main-thread stall. Keep one bounded append margin above that complete batch;
 // crossing either limit replaces the MSE epoch instead of dropping fragments.
@@ -284,6 +285,7 @@ export function MseFmp4WebSocketPlayer({
     let onBufferError: (() => void) | null = null;
     let objectUrl = "";
     let retryTimer: number | undefined;
+    let bufferingNoticeTimer: number | undefined;
     let receivedMedia = false;
     let failed = false;
     let playingReported = false;
@@ -295,10 +297,15 @@ export function MseFmp4WebSocketPlayer({
     );
     const queue: ArrayBuffer[] = [];
     let queuedBytes = 0;
+    const clearBufferingNotice = () => {
+      if (bufferingNoticeTimer !== undefined) window.clearTimeout(bufferingNoticeTimer);
+      bufferingNoticeTimer = undefined;
+    };
 
     const fail = (copy: string) => {
       if (!transportIsCurrent() || failed) return;
       startupWatchdog?.clear();
+      clearBufferingNotice();
       failed = true;
       transportHealthyRef.current = false;
       recoveryPendingAuthorityRef.current = null;
@@ -335,6 +342,7 @@ export function MseFmp4WebSocketPlayer({
         return;
       }
       startupWatchdog?.clear();
+      clearBufferingNotice();
       failed = true;
       transportHealthyRef.current = false;
       const retry = consumeCameraLeaseRetry(leaseRetryRef.current, delivery.id);
@@ -392,6 +400,7 @@ export function MseFmp4WebSocketPlayer({
 
     const onPlaying = () => {
       if (!transportIsCurrent() || failed) return;
+      clearBufferingNotice();
       startupWatchdog?.markPlaying();
       transportHealthyRef.current = true;
       leaseRetryRef.current = resetCameraLeaseRetryBudget(delivery.id);
@@ -410,7 +419,21 @@ export function MseFmp4WebSocketPlayer({
       }
     };
 
+    const onWaiting = () => {
+      if (!transportIsCurrent() || failed || !playingReported) return;
+      // A short receipt gap must not flicker or restart the acquisition-owned
+      // stream. A sustained decoder wait must not retain a playing presentation.
+      if (bufferingNoticeTimer !== undefined) return;
+      bufferingNoticeTimer = window.setTimeout(() => {
+        bufferingNoticeTimer = undefined;
+        if (!transportIsCurrent() || failed || video.readyState >= 3) return;
+        setStatus("buffering");
+        setMessage("Ожидание новых кадров.");
+      }, CAMERA_BUFFERING_NOTICE_DELAY_MS);
+    };
     video.addEventListener("playing", onPlaying);
+    video.addEventListener("waiting", onWaiting);
+    video.addEventListener("stalled", onWaiting);
 
     const appendNext = () => {
       if (
@@ -594,10 +617,13 @@ export function MseFmp4WebSocketPlayer({
       disposed = true;
       transportHealthyRef.current = false;
       startupWatchdog?.clear();
+      clearBufferingNotice();
       if (retryTimer !== undefined) window.clearTimeout(retryTimer);
       queue.length = 0;
       socket?.close(1000, "Browser preview transport replaced or hidden");
       video.removeEventListener("playing", onPlaying);
+      video.removeEventListener("waiting", onWaiting);
+      video.removeEventListener("stalled", onWaiting);
       mediaSource.removeEventListener("sourceopen", onSourceOpen);
       if (sourceBuffer && onBufferUpdateEnd) {
         sourceBuffer.removeEventListener("updateend", onBufferUpdateEnd);
@@ -708,7 +734,7 @@ export function MseFmp4WebSocketPlayer({
       {status !== "playing" ? (
         <div className="mse-fmp4-player__status" role="status" aria-live="polite">
           <Icon name={status === "error" ? "alert" : "video"} size={20} />
-          <strong>{status === "error" ? "Канал прерван" : "Подготовка камеры"}</strong>
+          <strong>{status === "error" ? "Канал прерван" : status === "buffering" ? "Ожидание изображения" : "Подготовка камеры"}</strong>
           <span>{message}</span>
           {status === "error" ? (
             <button