Validate action translation placeholders

[epenet]

Proposed change

Ensure that description placeholders are valid in action translations.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
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• This PR fixes or closes issue: fixes #
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[jbouwh]

Nice work, LGTM,
Thanks @epenet 👍

[Copilot]

Pull request overview

This PR adds validation checks for action (service) translation placeholders during test execution. It ensures that when services are registered with description_placeholders, the corresponding translations contain valid placeholder references.

Key changes:

• Added support for validating translation placeholders when service registration includes description_placeholders
• Extended _validate_translation to handle wildcard validation using trailing "." notation for checking all subkeys
• Patched ServiceRegistry.async_register to automatically validate service translation placeholders during tests