[AiBundle] Add missing symfony/ai-open-ai-platform dev dependency

The options.php file uses PlatformFactory::REGION_EU and REGION_US
constants from the OpenAI bridge package for configuration validation.

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

Author: OskarStark

src/ai-bundle/composer.json

@@ -35,6 +35,7 @@
         "phpstan/phpstan": "^2.1",
         "phpstan/phpstan-strict-rules": "^2.0",
         "phpunit/phpunit": "^11.5.46",
+        "symfony/ai-anthropic-platform": "@dev",
         "symfony/ai-azure-search-store": "@dev",
         "symfony/ai-cache-store": "@dev",
         "symfony/ai-chroma-db-store": "@dev",
@@ -47,6 +48,7 @@
         "symfony/ai-milvus-store": "@dev",
         "symfony/ai-mongo-db-store": "@dev",
         "symfony/ai-neo4j-store": "@dev",
+        "symfony/ai-open-ai-platform": "@dev",
         "symfony/ai-open-search-store": "@dev",
         "symfony/ai-pinecone-store": "@dev",
         "symfony/ai-postgres-store": "@dev",