build(deps): Update openai-php/client requirement || ^0.19

Updates the requirements on [openai-php/client](https://github.com/openai-php/client) to permit the latest version.
- [Release notes](https://github.com/openai-php/client/releases)
- [Changelog](https://github.com/openai-php/client/blob/main/CHANGELOG.md)
- [Commits](openai-php/client@v0.18.0...v0.19.0)

---
updated-dependencies:
- dependency-name: openai-php/client
  dependency-version: 0.19.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

composer.json

@@ -23,7 +23,7 @@
         "guzzlehttp/psr7": "^2.8",
         "illuminate/collections": "^12.49",
         "laravel/prompts": "^0.3.8",
-        "openai-php/client": "^0.18",
+        "openai-php/client": "^0.19",
         "php-mcp/client": "^1.0",
         "psr-discovery/cache-implementations": "^1.2",
         "psr-discovery/event-dispatcher-implementations": "^1.1",