ui: visual polish — animations, icons, and interaction improvements

- Spin animation on ⟳ delivery status during SENDING/ENCRYPTING states
- Pulsing ● dot on PTT LIVE badge (pttLivePulse keyframe)
- Read receipt pill: hover scale/opacity transition, symmetric padding
- PiP resize handles: larger dots (5px), wider hit area (24px), higher contrast
- ForwardMessageDialog: position:relative on scroll container, spinner overlay 0.35 opacity
- Boot sequence: 45ms interval (was 65ms), brighter ESC hint (0.55 opacity)
- Location button: Icons.Pin → Icons.SpaceGlobe (globe icon)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/features/room/message/ForwardMessageDialog.tsx

@@ -162,7 +162,7 @@ export function ForwardMessageDialog({ mEvent, onClose }: Props) {
                 <Text size="T300">✓ Forwarded to {sentTo}</Text>
               </Box>
             ) : (
-              <Box grow="Yes" style={{ minHeight: 0 }}>
+              <Box grow="Yes" style={{ minHeight: 0, position: 'relative' }}>
                 <Scroll size="300" hideTrack visibility="Hover">
                   <Box direction="Column" gap="100" style={{ padding: config.space.S200 }}>
                     {filtered.slice(0, 60).map((room) => (
@@ -195,7 +195,7 @@ export function ForwardMessageDialog({ mEvent, onClose }: Props) {
                     style={{
                       position: 'absolute',
                       inset: 0,
-                      background: 'rgba(0,0,0,0.18)',
+                      background: 'rgba(0,0,0,0.35)',
                       borderRadius: config.radii.R500,
                     }}
                   >