[#548] Move OTel sample from JS repository

[ceciliaavila]

Fixes #548

This pull request introduces a new OpenTelemetry (OTel) instrumented agent sample for Node.js, called OTelAgent, to the samples directory. The sample demonstrates how to integrate OpenTelemetry tracing, metrics, and logs into a Microsoft 365 Agent, and export telemetry to the .NET Aspire Dashboard. The changes include all source code, configuration, documentation, and build scripts needed to run and understand the sample.

Addition of OTelAgent sample:

• Added a new sample, OTelAgent, with its own directory, demonstrating end-to-end OpenTelemetry instrumentation in a Node.js Microsoft 365 Agent. The sample includes custom spans, counters, histograms, and enrichment for HTTP operations. (samples/nodejs/README.md, samples/nodejs/otel/README.md) [1] [2]

Source code and instrumentation:

• Implemented the core agent logic in agent.ts, including message handling, welcome messages, and telemetry events for both. (samples/nodejs/otel/src/agent.ts)
• Added agentTelemetry.ts to define and export custom OpenTelemetry metrics and tracers used by the agent. (samples/nodejs/otel/src/agentTelemetry.ts)
• Created instrumentation.ts to configure and initialize the OpenTelemetry SDK, supporting both OTLP and console exporters, and handling graceful shutdown. (samples/nodejs/otel/src/instrumentation.ts)

Configuration and build:

• Provided a template environment file (env.TEMPLATE) with all necessary configuration keys for authentication and telemetry export. (samples/nodejs/otel/env.TEMPLATE)
• Added a dedicated package.json with all dependencies and build/start scripts for the sample. (samples/nodejs/otel/package.json)
• Included a tsconfig.json for TypeScript compilation targeting Node.js. (samples/nodejs/otel/tsconfig.json)

Testing

This image shows the traces exported by the sample.