fix: resolve TypeScript errors in mini-map and layer-effects-panel

- Add null check for layer.canvas before drawing in mini-map
- Change JSX.Element to React.ReactElement in layer-effects-panel
- Fixes deployment build errors

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

components/layers/layer-effects-panel.tsx

@@ -34,7 +34,7 @@ const EFFECT_NAMES: Record<EffectType, string> = {
   satin: 'Satin',
 };
 
-const EFFECT_ICONS: Record<EffectType, JSX.Element> = {
+const EFFECT_ICONS: Record<EffectType, React.ReactElement> = {
   dropShadow: <Sparkles className="h-3 w-3" />,
   innerShadow: <Sparkles className="h-3 w-3" />,
   outerGlow: <Sparkles className="h-3 w-3" />,