fix(shape-css): add pointer-events:all to header/toolbar; fix hardcoded white on lock icon

- .cc-shape-header and .cc-shape-toolbar button were missing pointer-events:all,
  causing toolbar buttons to be unclickable inside tldraw canvas
- Replace color:'white' on lock indicator with var(--cc-text-inverse)

src/utils/tldraw/cc-base/CCBaseShapeUtil.tsx

@@ -82,7 +82,7 @@ export abstract class CCBaseShapeUtil<T extends CCBaseShape> extends BaseBoxShap
                 </div>
               </button>
             ))}
-            {isLocked && <span style={{ color: 'white' }}>🔒</span>}
+            {isLocked && <span style={{ color: 'var(--cc-text-inverse)' }}>🔒</span>}
           </div>
         </div>
         {/* Content */}