perf(bundle): dynamic-import iptv-playlist-parser to drop 130KB validator from eager bundle

iptv-playlist-parser statically imports the entire validator library
(~130KB across 113 files). Because PlaylistsService is eager (re-exported
through the 'services' barrel that AppComponent imports), validator was
landing in the cold-start preloaded chunk even though parse() only runs
on user-triggered playlist imports (FILE/URL/TEXT add).

Switch handlePlaylistParsing() to dynamic-import the parser. The two
callers (playlist-backup.service and the parsePlaylist$ NgRx effect)
needed minor adjustments — the effect now uses mergeMap(from(...)) to
flatten the Promise back into the action stream.

Cold-start preloaded chunk: 1511KB -> 1374KB (-9%).
Validator now sits in a separate ~129KB chunk that loads only when
the user adds a playlist.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Entire-Checkpoint: 3ec205264762

libs/m3u-state/src/lib/effects.ts

@@ -11,7 +11,9 @@ import {
     EMPTY,
     filter,
     firstValueFrom,
+    from,
     map,
+    mergeMap,
     switchMap,
     tap,
     withLatestFrom,
@@ -277,12 +279,14 @@ export class PlaylistEffects {
     parsePlaylist$ = createEffect(() => {
         return this.actions$.pipe(
             ofType(PlaylistActions.parsePlaylist),
-            map((action) =>
-                this.playlistsService.handlePlaylistParsing(
-                    action.uploadType,
-                    action.playlist,
-                    action.title,
-                    action.path
+            mergeMap((action) =>
+                from(
+                    this.playlistsService.handlePlaylistParsing(
+                        action.uploadType,
+                        action.playlist,
+                        action.title,
+                        action.path
+                    )
                 )
             ),
             map((playlist) =>

libs/services/src/lib/playlist-backup.service.ts

@@ -610,7 +610,7 @@ export class PlaylistBackupService {
         playlistId: string,
         existing: Playlist | null
     ): Promise<Playlist> {
-        const parsedPlaylist = this.playlistsService.handlePlaylistParsing(
+        const parsedPlaylist = await this.playlistsService.handlePlaylistParsing(
             'TEXT',
             entry.source.rawM3u,
             entry.title

libs/services/src/lib/playlists.service.ts

@@ -2,7 +2,6 @@
 import { inject, Injectable } from '@angular/core';
 import { MatSnackBar } from '@angular/material/snack-bar';
 import { TranslateService } from '@ngx-translate/core';
-import { parse } from 'iptv-playlist-parser';
 import {
     aggregateFavoriteChannels,
     createFavoritesPlaylist,
@@ -760,13 +759,17 @@ export class PlaylistsService {
         );
     }
 
-    handlePlaylistParsing(
+    async handlePlaylistParsing(
         uploadType: 'FILE' | 'URL' | 'TEXT',
         playlist: string,
         title: string,
         path?: string
     ) {
         try {
+            // Dynamic import keeps the ~130KB validator dep (transitively pulled
+            // by iptv-playlist-parser) out of the eager bundle. parse() only runs
+            // on user-triggered imports.
+            const { parse } = await import('iptv-playlist-parser');
             const parsedPlaylist = parse(playlist);
             return createPlaylistObject(
                 title,