Support Spring Boot property conventions for API key configuration

[alexheifetz]

Problem

Need to Configure API keys via application.yml with environment variable overrides

Use Case

Developers should be able to pull a repo and run it without configuration. Local defaults (e.g., dev API key pointing to a rate-limited gateway) live in application.yml; production credentials are injected via environment variables at deployment.

Proposed Solution

Support Spring Boot mechanism:

openai:
   api-key: ${OPENAI_API_KEY:sk-dev-key}

[alexheifetz]

This feature has been implemented for Open AI Models. API key maybe set via environmental variable or by property to application configuration.

embabel.agent.platform.models.openai.api-key

[alexheifetz]

Anthropic and other models will be supported shortly.