fix(playback): keep MPV/VLC rows of the live tab confirmable by URL

The live tab's session key can only be confirmed by its own inline
players; MPV/VLC confirm the launched URL alone. A row that goes to an
external player (also later, after a double-click) now defers by URL, and
only rows played inline carry the session key.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/architecture/embedded-inline-playback.md

@@ -1149,9 +1149,10 @@ reaches history.
 - Matching: a write deferred with a session key is confirmed only by that
   same key — the same URL in two playlists must not let playback in one
   (inline, or in MPV/VLC) record a failed attempt in the other. Writes
-  without one (portal resolvers, collection tabs) match any confirmation of
-  their stream URL. The global live tab defers with its own
-  playlist-scoped session key, which also survives a switch to catch-up.
+  without one (portal resolvers) match any confirmation of their stream URL.
+  The global live tab defers with its own playlist-scoped session key, which
+  also survives a switch to catch-up, when the row plays inline; a row that
+  goes to MPV/VLC defers by URL, the only thing that launch confirms.
 - `WebPlayerViewComponent` confirms its `playbackSessionKey`, `streamUrl`
   and `playback.streamUrl` once the owned engine's reported position has
   advanced by 2 seconds while playing (`PlaybackProgressConfirmation`).

libs/portal/shared/ui/src/lib/components/unified-collection/unified-live-selection.ts

@@ -248,13 +248,20 @@ export function createUnifiedLiveSelection(options: {
             }
 
             // Selecting a channel is not watching it: the row moves to the
-            // top of Recently Viewed once its stream has really played. The
-            // tab's playlist-scoped session key — the one its players confirm
-            // with — survives a switch to catch-up and does not match the
-            // same URL listed in another playlist.
+            // top of Recently Viewed once its stream has really played. Played
+            // inline, the tab's playlist-scoped session key — the one its
+            // players confirm with — survives a switch to catch-up and does
+            // not match the same URL in another playlist. MPV/VLC can only
+            // confirm the launched URL, so an external row defers by URL.
+            const playsInline = !options.shouldOpenExternalPlayback(
+                detail,
+                true
+            );
             historyGate.defer(
                 {
-                    sessionKey: createUnifiedLivePlaybackSessionKey(item),
+                    sessionKey: playsInline
+                        ? createUnifiedLivePlaybackSessionKey(item)
+                        : null,
                     streamUrls: [detail.playback.streamUrl],
                 },
                 () => void recordLivePlayback(item)

libs/portal/shared/ui/src/lib/components/unified-collection/unified-live-tab.fullscreen-panel.spec.ts

@@ -175,7 +175,8 @@ describe('UnifiedLiveTabComponent fullscreen channel panel', () => {
         }
     );
 
-    it('correlates a row with its session key, not its stream URL', async () => {
+    it('correlates an inline row with its session key, not its stream URL', async () => {
+        portalPlayer.isEmbeddedPlayer.mockReturnValue(true);
         const item = buildM3uLiveItem();
         streamResolver.resolveM3uPlaybackDetail.mockResolvedValue({
             epgMode: 'm3u',
@@ -206,6 +207,29 @@ describe('UnifiedLiveTabComponent fullscreen channel panel', () => {
         expect(recentData.recordLivePlayback).toHaveBeenCalledWith(item);
     });
 
+    it('records a row played in MPV/VLC from the URL its launch confirms', async () => {
+        const item = buildM3uLiveItem();
+        streamResolver.resolveM3uPlaybackDetail.mockResolvedValue({
+            epgMode: 'm3u',
+            playback: { streamUrl: item.streamUrl, title: item.name },
+            epgPrograms: [],
+        });
+        recentData.recordLivePlayback.mockResolvedValue(item);
+        fixture.componentRef.setInput('items', [item]);
+        fixture.detectChanges();
+        await fixture.whenStable();
+        await component.onChannelSelected(component.channelsForList()[0]);
+        expect(portalPlayer.openResolvedPlayback).toHaveBeenCalled();
+
+        // The external session update carries only the launched URL.
+        TestBed.inject(PlaybackHistoryGate).confirm({
+            streamUrls: [item.streamUrl],
+        });
+        await fixture.whenStable();
+
+        expect(recentData.recordLivePlayback).toHaveBeenCalledWith(item);
+    });
+
     it('moves a row that played to the top of Recently Viewed after another row was selected', async () => {
         const first = buildM3uLiveItem();
         const second: UnifiedCollectionItem = {