feat : MCP server infrastructure setup

Install symfony/mcp-bundle, add STDIO + HTTP transport config,
API token auth on User entity with custom authenticator and firewall,
generate-api-token console command, Nginx /_mcp location, fixture token.

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

composer.json

@@ -14,7 +14,7 @@
         "doctrine/orm": "^3.6",
         "lexik/jwt-authentication-bundle": "^3.2",
         "nelmio/cors-bundle": "^2.6",
-        "phpdocumentor/reflection-docblock": "^6.0",
+        "phpdocumentor/reflection-docblock": "^5.6|^6.0",
         "phpstan/phpdoc-parser": "^2.3",
         "symfony/asset": "8.0.*",
         "symfony/console": "8.0.*",
@@ -23,6 +23,7 @@
         "symfony/flex": "^2",
         "symfony/framework-bundle": "8.0.*",
         "symfony/http-client": "8.0.*",
+        "symfony/mcp-bundle": "^0.6.0",
         "symfony/property-access": "8.0.*",
         "symfony/property-info": "8.0.*",
         "symfony/runtime": "8.0.*",