fix: refresh stale proxy token on video error

static/player/source.ts

@@ -1,4 +1,7 @@
 import { state } from "./state";
+import { safeLocalStorage } from "./storage";
+import { isRecord, parseModeSources } from "./validate";
+import { loadVideoSource } from "./video";
 
 export const streamUrlForMode = (mode: string, quality?: string): string => {
   const src = state.playback.modeSources[mode];
@@ -16,3 +19,30 @@ export const streamUrlForMode = (mode: string, quality?: string): string => {
 
   return url;
 };
+
+export const refreshCurrentModeSource = async (signal?: AbortSignal): Promise<boolean> => {
+  const mode = state.playback.currentMode;
+  const res = await fetch(
+    `/api/watch/episode/${state.episode.malID}/${encodeURIComponent(state.episode.current)}?mode=${encodeURIComponent(mode)}`,
+    { signal },
+  );
+  if (!res.ok) {
+    throw new Error(`mode source refresh failed with status ${res.status}`);
+  }
+
+  const data: unknown = await res.json();
+  if (!isRecord(data)) {
+    return false;
+  }
+
+  const refreshedSource = parseModeSources(data.mode_sources)[mode];
+  if (!refreshedSource?.token) {
+    return false;
+  }
+
+  state.playback.modeSources = { ...state.playback.modeSources, [mode]: refreshedSource };
+
+  const preferredQuality = safeLocalStorage.getItem("mal:preferred-quality") || "best";
+  loadVideoSource(streamUrlForMode(mode, preferredQuality), refreshedSource.type);
+  return true;
+};