feat(embedded-mpv): configurable extra libmpv options and network auto-reconnect (#1515)

Extra libmpv options (Settings > Playback) reach every embedded engine off the command line (createSession array on Windows/macOS, a 0600 --include file on Linux native-view, a stdin preamble for the frame-copy helper); the keys the embed depends on are refused, and keys libmpv rejects are reported once per session. Dropped streams reload automatically (error, or ended on live) with 2 s -> 30 s backoff, six attempts per outage and a 30 s stability reset, only for a load that already played; engine failures stay terminal, a running recording is filed as interrupted and restarted after the reload, and an external subtitle file is re-added. Settings.embeddedMpvAutoReconnect (default on) opts out; the player shows 'Reconnecting... attempt N of M'.

Started by Bpl5966 in #1515 and finished by the maintainers in the same PR.

Co-authored-by: Bpl5966 <amine.b1959@gmail.com>
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

libs/shared/interfaces/src/lib/embedded-mpv-session.interface.ts

@@ -2,13 +2,7 @@ import type { PlayerSubtitleStyle } from './subtitle-style.util';
 import type { RecordingStartMetadata } from './recording-metadata.interface';
 
 export type EmbeddedMpvSessionStatus =
-    | 'idle'
-    | 'loading'
-    | 'playing'
-    | 'paused'
-    | 'ended'
-    | 'error'
-    | 'closed';
+    'idle' | 'loading' | 'playing' | 'paused' | 'ended' | 'error' | 'closed';
 
 export interface EmbeddedMpvBounds {
     x: number;
@@ -129,4 +123,19 @@ export interface EmbeddedMpvSession {
     startedAt: string;
     updatedAt: string;
     error?: string;
+    /**
+     * Present while the main process is waiting to reload a dropped stream
+     * or has such a reload in flight; absent once playback is back or the
+     * attempts are exhausted. Display only — the renderer never schedules.
+     */
+    reconnect?: EmbeddedMpvReconnectInfo;
+}
+
+/** Progress of the main-process automatic reconnect for one session. */
+export interface EmbeddedMpvReconnectInfo {
+    /** 1-based number of the attempt that is scheduled or in flight. */
+    attempt: number;
+    maxAttempts: number;
+    /** ISO timestamp at which the scheduled attempt fires. */
+    nextAttemptAt: string;
 }