Fix SQS MessageInterceptor exceptions handling

[tomazfernandes]

Why

Closes #1595

When a MessageInterceptor throws an exception, the MessageListenerExecutionStage is never reached, so the exception never gets wrapped in ListenerExecutionFailedException. All downstream pipeline stages (ErrorHandler, after-processing interceptors, AcknowledgementHandler) expect to unwrap a message from the exception chain and fail with IllegalArgumentException: No ListenerExecutionFailedException found to unwrap messages.

This breaks valid use cases like interceptor-based idempotency checks that rely on the ErrorHandler to gracefully handle rejection.

What

• Introduce MessageProcessingException interface as a common marker for exceptions that carry message references through the processing pipeline
• Add InterceptorExecutionFailedException for failures in before-processing interceptors
• ListenerExecutionFailedException now implements MessageProcessingException; static utility methods deprecated in favour of MessageProcessingException equivalents

How

• Wrap interceptor exceptions in InterceptorExecutionFailedException via exceptionallyCompose in AbstractBeforeProcessingInterceptorExecutionStage (both single and batch paths)
• Update all downstream stages (ErrorHandlerExecutionStage, AbstractAfterProcessingInterceptorExecutionStage, AcknowledgementHandlerExecutionStage) to use MessageProcessingException for unwrapping
• Update observation adapter in AsyncComponentAdapters to preserve exception type when re-wrapping with updated message headers

Acceptance Criteria

• Interceptor exceptions wrapped in InterceptorExecutionFailedException with message reference
• ErrorHandler.handle() invoked for interceptor failures (single and batch)
• After-processing interceptors called on interceptor failure
• AcknowledgementHandler works correctly for interceptor failures
• Both blocking and async interceptor paths covered
• Observation adapter preserves exception type when re-wrapping
• No regression in existing tests
• Pipeline composition order unchanged

Testing

• Updated unit tests in BeforeProcessingInterceptorExecutionStageTests and BeforeProcessingContextInterceptorExecutionStageTests to assert InterceptorExecutionFailedException with correct message references
• Added integration tests verifying ErrorHandler and afterProcessing interceptor invocation when an interceptor throws (single and batch paths)
• Added integration test verifying end-to-end recovery: interceptor throws → error handler swallows → message acknowledged → listener never called

[tomazfernandes]

CI tests failing due to #1586

Tests pass locally: