camel-openai: close OpenAI client on endpoint stop to prevent OkHttp thread leak

[Croway]

Summary

• Call client.close() in OpenAIEndpoint.doStop() before nulling the reference so that OkHttp's dispatcher executor, connection pool, and cache are properly shut down.
• Without this, OkHttp threads (OkHttp Dispatcher, OkHttp ConnectionPool) linger after route stop, especially visible under exec:java or Camel JBang dev mode where the JVM does not exit.

[github-actions]

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[github-actions]

🧪 CI tested the following changed modules:

• components/camel-ai/camel-openai

⚠️ Some tests are disabled on GitHub Actions (@DisabledIfSystemProperty(named = "ci.env.name")) and require manual verification:

• components/camel-ai/camel-openai: 6 test(s) disabled on GitHub Actions

All tested modules (8 modules)

• Camel :: AI :: OpenAI
• Camel :: JBang :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: TUI
• Camel :: JBang :: Plugin :: Validate
• Camel :: Launcher :: Container
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin

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[apupier]

Should we enclose in a try catch as it is done for the mcp clients?

[Croway]

Closes this client, relinquishing any underlying resources.
This is purposefully not inherited from AutoCloseable because the client is long-lived and usually should not be synchronously closed via try-with-resources.

this is from the .close() java doc, should be safe without a try catch

[gnodet]

Correct fix — calling client.close() before setting client = null in OpenAIEndpoint.doStop() ensures the HTTP client resources are properly released. Without this, the client would be leaked on endpoint stop.

LGTM.

Fully automatic review from Claude Code