Clean root vendor after build-packages to avoid circular symlinks

The build-packages.php script updates composer.json files to use path
repositories, which create symlinks. When a platform bridge depends on
symfony/ai-platform, the symlink points to src/platform which contains
the bridges themselves, creating recursive symlinks that cause
"Too many levels of symbolic links" errors in PHPStan.

By removing the root vendor directory after build-packages.php runs,
we ensure the symlinks don't cause issues when installing bridge
dependencies.

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

Author: OskarStark

.github/workflows/code-quality.yaml

@@ -182,6 +182,11 @@ jobs:
               if: matrix.bridge.component == 'platform'
               run: php .github/build-packages.php
 
+            # Remove root vendor to avoid circular symlinks when installing bridge dependencies
+            - name: Clean root vendor (platform bridges only)
+              if: matrix.bridge.component == 'platform'
+              run: rm -rf vendor
+
             - name: Install dependencies
               uses: ramsey/composer-install@v3
               with:

.github/workflows/unit-tests.yaml

@@ -303,6 +303,10 @@ jobs:
             - name: Build packages
               run: php .github/build-packages.php
 
+            # Remove root vendor to avoid circular symlinks when installing bridge dependencies
+            - name: Clean root vendor
+              run: rm -rf vendor
+
             - name: Install dependencies
               uses: ramsey/composer-install@v3
               with: