CAMEL-23184: Deprecate camel-splunk component

[oscerd]

Summary

• Deprecate the camel-splunk component since the Splunk Java SDK it depends on is no longer actively maintained, and the ServiceMix bundle wrapping it is also stale.
• Added @Deprecated(since = "4.19") to all public Java classes
• Updated documentation with deprecation notice and Stable-deprecated support level
• Added entry to the 4.19 upgrade guide
• Regenerated catalog and DSL artifacts

Note: camel-splunk-hec is NOT deprecated — it uses standard HTTP client (httpclient5) directly, with no dependency on the dead SDK.

JIRA: https://issues.apache.org/jira/browse/CAMEL-23184

Claude Code on behalf of Andrea Cosentino

🤖 Generated with Claude Code

[github-actions]

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