CAMEL-23282: fix unbounded BeanInfo cache growth for body OGNL expressions

[Croway]

Summary

• Always use class-based BeanInfo cache keys instead of instance-based keys
• Introspection results depend on the class type, not the instance identity
• Instance-based keys caused cache pollution (1000 duplicate entries for 1 class) and memory leaks for ephemeral message bodies used with OGNL expressions like ${body.name}

Test plan

• New BeanInfoCacheBodyOgnlTest validates cache stays at 1 entry across multiple messages with body class that has Exchange parameter methods
• Existing BeanInfoCacheExchangeTest passes
• All tests pass
• • core/camel-core
• • core/camel-management
• • components/camel-mybatis
• • components/camel-aws/camel-aws-xray
• • components/camel-test/camel-test-junit5
• • dsl/camel-kamelet-main
• • components/camel-bean
• • core/camel-main

[github-actions]

🌟 Thank you for your contribution to the Apache Camel project! 🌟
🤖 CI automation will test this PR automatically.

🐫 Apache Camel Committers, please review the following items:

• First-time contributors require MANUAL approval for the GitHub Actions to run
• You can use the command /component-test (camel-)component-name1 (camel-)component-name2.. to request a test from the test bot although they are normally detected and executed by CI.
• You can label PRs using build-all, build-dependents, skip-tests and test-dependents to fine-tune the checks executed by this PR.
• Build and test logs are available in the summary page. Only Apache Camel committers have access to the summary.

⚠️ Be careful when sharing logs. Review their contents before sharing them publicly.