fix(starter): set CSS Modules to local mode for webpack compatibility

Next.js 16 defaults CSS Modules to pure mode, which rejects global
element selectors used to scope WordPress block styles. Set mode to
local and add empty turbopack config to support both build modes.

Author: josephfusco

examples/next/faustwp-getting-started/next.config.js

@@ -25,4 +25,26 @@ module.exports = withFaust({
       xssProtection: false
     }) }];
   },
+  turbopack: {},
+  webpack: (config) => {
+    // Use 'local' mode for CSS Modules to allow global element selectors
+    // (e.g. :global(.component *) figure { ... }) which fail in 'pure' mode.
+    const oneOfRule = config.module.rules.find((rule) => rule.oneOf);
+    if (oneOfRule) {
+      oneOfRule.oneOf.forEach((rule) => {
+        if (Array.isArray(rule.use)) {
+          rule.use.forEach((loader) => {
+            if (
+              typeof loader === 'object' &&
+              loader.loader?.includes('css-loader') &&
+              loader.options?.modules
+            ) {
+              loader.options.modules.mode = 'local';
+            }
+          });
+        }
+      });
+    }
+    return config;
+  },
 });