Made copy-styles safer

Replaced `;` with `&&` for chaining copying commands. This means copy-styles will return a fail code if it doesn't copy to esm correctly.

package.json

@@ -22,7 +22,7 @@
     "build": "npm run clean && npm run build:esm && npm run build:cjs && npm run build:copy-styles && npm run build:example",
     "build:esm": "tsc",
     "build:cjs": "tsc --module commonjs --outDir ./dist/cjs",
-    "build:copy-styles": "cp -r ./src/style ./dist/esm; cp -r ./src/style ./dist/cjs",
+    "build:copy-styles": "cp -r ./src/style ./dist/esm && cp -r ./src/style ./dist/cjs",
     "build:example": "(cd ./example && tsc && vite build)",
     "test": "tsc && npm run format:check && npm run test:integration",
     "test:integration": "BROWSER=none jest --maxWorkers=1 -c jest.config.js",