Two related VoiceBar / scaffold issues on wide windows:
1. Banner placement
The 'not production ready' tertiaryContainer banner sat full-width
above the body Column. In wide layouts (>=840 dp) where the connected
view splits into Voice Bar (320 dp) + channel tree (Expanded), the
banner spanned both columns and dwarfed the channel-tree pane.
Rework: wrap the body in an outer LayoutBuilder so the placement
decision can read bodyConstraints.maxWidth. When wide AND connected
AND snapshot != null, render the banner inside the left 320 dp
SizedBox above the VoiceBar. In every other state (narrow, idle,
connecting) the banner stays pinned full-width at the top.
2. Channel-name pill overflow
The Container holding the channel pill had no width constraint and
Text(channelName) had no overflow handling. Long channel names made
the pill extend past the column's 320 dp; mute icons slid under the
adjacent channel tree.
Rework: pill wrapped in Flexible(flex: 100, fit: FlexFit.loose);
inner Text gets maxLines: 1, overflow: TextOverflow.ellipsis,
softWrap: false. Spacer keeps default flex 1; the 100:1 ratio means
short names hug their intrinsic width and long names take ~99% of
the remaining space then ellipsize. Mute icons stay pinned right.
flutter analyze: clean (6 pre-existing Radio.groupValue infos only).