refactor: Move publish logic to lib/publishPackages.ts and call directly

Extract the tarball publishing logic into an importable function in
lib/publishPackages.ts and call it directly from registrySetup instead
of spawning a subprocess. Remove the old publish-packages.ts script.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mydea

dev-packages/e2e-tests/lib/publishPackages.ts

@@ -10,8 +10,9 @@ const repositoryRoot = path.resolve(__dirname, '../../..');
  * Publishes all built Sentry package tarballs to the local Verdaccio test registry.
  */
 export function publishPackages(): void {
-  const version = (JSON.parse(readFileSync(path.join(__dirname, '../package.json'), 'utf8')) as { version: string })
-    .version;
+  const version = (
+    JSON.parse(readFileSync(path.join(__dirname, '../package.json'), 'utf8')) as { version: string }
+  ).version;
 
   // Get absolute paths of all the packages we want to publish to the fake registry
   // Only include the current versions, to avoid getting old tarballs published as well