sitesmith: alias tiny-invariant to a diagnostic shim

The prod build of tiny-invariant strips all failure messages, leaving
us with bare 'Error: Invariant failed' and no actionable info. Aliasing
the package to a shim that always emits the message + a stack-trace
console.error before throwing — so the next Craft.js invariant we hit
tells us which assertion (ERROR_NOT_IN_RESOLVER, ERROR_NOPARENT,
ERROR_INVALID_NODE_ID, etc.) is actually failing.

Temporary; will revert once the Sitesmith apply flow is stable.

craft/vite.config.ts

@@ -8,6 +8,9 @@ export default defineConfig({
   resolve: {
     alias: {
       '@': path.resolve(__dirname, './src'),
+      // Diagnostic: replace tiny-invariant with a shim that always logs the
+      // failure message (the upstream prod build strips it).
+      'tiny-invariant': path.resolve(__dirname, './src/utils/tiny-invariant-shim.ts'),
     },
   },
   build: {