CAMEL-23312: Add SpanKind support to OpenTelemetry2 component

[JiriOndrusek]

fixes https://issues.apache.org/jira/browse/CAMEL-23312
superseeds #22612

Adds SpanKind parameter to the Camel telemetry API to enable proper span type classification (CLIENT, SERVER, PRODUCER, CONSUMER, INTERNAL) across different observability backends.

Changes

• SpanDecorator API: Added getSpanKind(String operation) method to allow decorators to specify appropriate span kinds based on operation type
• SpanLifecycleManager: Updated create() signature to accept spanKind parameter
• Tracer: Modified to pass spanKind from decorator to lifecycle manager during span creation
• OpenTelemetryTracer: Implemented spanKind support using OpenTelemetry's SpanKind enum
• SpanDecorator implementations:
  • AbstractHttpSpanDecorator: Returns CLIENT for EVENT_SENT, SERVER for EVENT_RECEIVED
  • AbstractMessagingSpanDecorator: Returns PRODUCER for EVENT_SENT, CONSUMER for EVENT_RECEIVED
  • AbstractSpanDecorator: Returns INTERNAL as default

Target

• I checked that the commit is targeting the correct branch (Camel 4 uses the main branch)

Tracking

• If this is a large change, bug fix, or code improvement, I checked there is a JIRA issue filed for the change (usually before you start working on it).

Apache Camel coding standards and style

• I checked that each commit in the pull request has a meaningful subject line and body.

• I have run mvn clean install -DskipTests locally from root folder and I have committed all auto-generated changes.

[github-actions]

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[github-actions]

🧪 CI tested the following changed modules:

• components/camel-micrometer-observability
• components/camel-opentelemetry2
• components/camel-telemetry-dev
• components/camel-telemetry

All tested modules (11 modules)

• Camel :: Common Telemetry
• Camel :: JBang :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: Validate
• Camel :: Launcher :: Container
• Camel :: Micrometer :: Observability 2
• Camel :: Observability Services
• Camel :: Opentelemetry 2
• Camel :: Telemetry :: Dev
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin

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⚙️ View full build and test results

[squakez]

Good work! A few notes to improve the overall readability of the code but the structure is good and compliant with the design.

[davsclaus]

LGTM

[apupier]

I think it is not but just to double-check: this interface is not supposed ot be used outside of camel core?
If yes, would need to add a note in the upgrade guide

[squakez]

Good point, although I doubt anybody is implementing any custom component. However to be consistent we need to add a minor note as you suggest, but more important, we need to change the documentation in https://camel.apache.org/components/next/others/telemetry.html#_implementation_specific_abstraction to include the new param.