Add panel discussions option to webinars and widen audience strip.

Webinars can enable multi-speaker stage layout at creation or on the details page; plenary view shows 12 attendee avatars before the overflow count.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/Feature/MeetWebTest.php

@@ -614,6 +614,30 @@ class MeetWebTest extends TestCase
         ]);
     }
 
+    public function test_host_can_enable_panel_discussions_on_webinar(): void
+    {
+        $this->actingAs($this->user)
+            ->post('/webinars', [
+                'title' => 'Panel webinar',
+                'scheduled_at' => now()->addDay()->format('Y-m-d\TH:i'),
+                'duration_minutes' => 60,
+                'panel_discussions' => '1',
+            ])
+            ->assertRedirect();
+
+        $room = Room::where('title', 'Panel webinar')->firstOrFail();
+        $this->assertTrue($room->setting('panel_discussions'));
+        $this->assertSame('plenary', $room->setting('stage_layout'));
+
+        $this->actingAs($this->user)
+            ->post(route('meet.webinars.settings.update', $room), [
+                'panel_discussions' => '0',
+            ])
+            ->assertRedirect(route('meet.webinars.show', $room));
+
+        $this->assertFalse($room->fresh()->setting('panel_discussions'));
+    }
+
     public function test_user_can_create_channel_and_post_message(): void
     {
         $this->actingAs($this->user)