fix: restore design-system files accidentally reverted in prior commit

Commit 669a661 had a stale staged deletion of cc-design-system.css and
reverted three other CSS-variable files. This commit restores them to
the state from cd37771 (adopt --cc-* CSS variable system).

src/utils/tldraw/cc-base/cc-transcription/CCLiveTranscriptionShapeUtil.tsx

@@ -83,7 +83,7 @@ export class CCLiveTranscriptionShapeUtil extends CCBaseShapeUtil<CCLiveTranscri
               height: '48px',
               borderRadius: '50%',
               border: 'none',
-              backgroundColor: isRecording ? '#f44336' : '#4CAF50',
+              backgroundColor: isRecording ? 'var(--cc-recording-active)' : 'var(--cc-recording-idle)',
               color: 'white',
               fontSize: '24px',
               cursor: 'pointer',
@@ -105,7 +105,7 @@ export class CCLiveTranscriptionShapeUtil extends CCBaseShapeUtil<CCLiveTranscri
             <div style={{ 
               fontSize: '16px', 
               fontWeight: 'bold',
-              color: isRecording ? '#f44336' : '#4CAF50'
+              color: isRecording ? 'var(--cc-recording-active)' : 'var(--cc-recording-idle)'
             }}>
               {isRecording ? 'Recording...' : 'Ready'}
             </div>