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/call/CallControls.tsx

@@ -218,7 +218,21 @@ export function CallControls({ callEmbed }: CallControlsProps) {
                 fontFamily: 'JetBrains Mono, monospace',
               }}
             >
-              {pttActive ? '● LIVE' : `PTT — Hold ${pttKeyLabel}`}
+              {pttActive ? (
+                <>
+                  <span
+                    style={{
+                      display: 'inline-block',
+                      animation: 'pttLivePulse 900ms ease-in-out infinite',
+                    }}
+                  >
+                    ●
+                  </span>
+                  {' LIVE'}
+                </>
+              ) : (
+                `PTT — Hold ${pttKeyLabel}`
+              )}
             </Text>
           </Box>
         ) : (