feat: Azure Event Hubs exporter

[fedeoliv]

Description

This PR adds a new exporter that sends traces, logs, and metrics to Azure Event Hubs.

Testing

• Added unit tests for configuration, factory, and marshallers
• Tested with different auth types (connection string, service principal, managed identities)
• Validated partition key strategies (random, static, resource_attribute, trace_id, span_id)

Documentation

• README with configuration examples
• Example configurations for all auth types

Features

• Supports multiple authentication methods (connection string, service principal, managed identities, workload identity, Default Azure credentials)
• Configurable Event Hub routing for traces, logs, and metrics
• Partition key strategies for load distribution
• JSON and Protobuf format support
• Retry configuration
• Event size validation (max 1MB based on the Azure Event Hubs quotas and limits documentation)

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: fedeoliv / name: Fernando de Oliveira (3f8df33, 7629c2c, be08d5e, c3f5be0, cb825a5, cee3fb3, f78442e)

[github-actions]

Welcome, contributor! Thank you for your contribution to opentelemetry-collector-contrib.

Important reminders:

• Please review our Contributing Guidelines.
• Don't forget to sign the Contributor License Agreement (CLA) if you haven't already.

A maintainer will review your pull request soon. Thank you for helping make OpenTelemetry better!

[constanca-m]

Hi @fedeoliv ! Thanks for your contribution!

The event hub has a kafka endpoint, and we currently have a kafka exporter. What would this exporter give us extra?

---

Regardless, there is a workflow to follow on new components:

1. Open an issue first to find a sponsor for your component.
2. Once you have a sponsor, open a first PR with only the skeleton of the new component.
3. Then you can open a 2nd PR (it would be this one) with the implementation.

Please see the contributing guide: Adding new components.

[constanca-m]

Please use azureauth extension

[github-actions]

Welcome, contributor! Thank you for your contribution to opentelemetry-collector-contrib.

Important reminders:

• Please review our Contributing Guidelines.
• Don't forget to sign the Contributor License Agreement (CLA) if you haven't already.

A maintainer will review your pull request soon. Thank you for helping make OpenTelemetry better!