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/Message.tsx

@@ -58,6 +58,7 @@ import { MessageLayout, MessageSpacing } from '../../../state/settings';
 import { useMatrixClient } from '../../../hooks/useMatrixClient';
 import { useRecentEmoji } from '../../../hooks/useRecentEmoji';
 import * as css from './styles.css';
+import { SendingSpinClass } from '../../../styles/Animations.css';
 import { EventReaders } from '../../../components/event-readers';
 import { ReadReceiptAvatars } from '../../../components/read-receipt-avatars';
 import { useReadPositions } from '../ReadPositionsContext';
@@ -127,7 +128,15 @@ function DeliveryStatus({
           : {}),
       }}
     >
-      {icon}
+      <span
+        className={
+          status === EventStatus.SENDING || status === EventStatus.ENCRYPTING
+            ? SendingSpinClass
+            : undefined
+        }
+      >
+        {icon}
+      </span>
     </Box>
   );
 }