[AiBundle][VertexAI] Fix service definition

[valtzu]

Q	A
Bug fix?	yes
New feature?	no
Docs?	no
Issues	Fix #419
License	MIT

Fix a couple of VertexAI issues:

1. Bundle config was not working at all since instances were created build-time instead of building Definitions
2. Access token was fetched build-time

To add tests, we'd need to add google/auth to dev dependencies. If that's ok, I'll do that and remove exclusion from phpstan.dist.neon.

[chr-hertel]

To add tests, we'd need to add google/auth to dev dependencies.

Yes please 👍

[chr-hertel]

@1ed can you confirm this patch works for you?

[Copilot]

Pull Request Overview

This PR fixes critical issues with the VertexAI service definition in the AI Bundle where the configuration wasn't working properly due to build-time instantiation instead of proper dependency injection definitions.

• Converts build-time credential fetching to proper service definitions using factories
• Replaces build-time HTTP client creation with dependency injection definitions
• Adds google/auth package to dev dependencies for testing

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/ai-bundle/src/AiBundle.php	Converts VertexAI platform setup from build-time instantiation to proper service definitions
src/ai-bundle/composer.json	Adds google/auth as dev dependency for testing
src/ai-bundle/tests/DependencyInjection/AiBundleTest.php	Adds VertexAI configuration to test suite

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[OskarStark]

Thanks for fixing this bug @valtzu.

[1ed]

@1ed can you confirm this patch works for you?

It works, thank you!