chore(opentelemetry-node)!: drop instrumentation-fastify

[trentm]

Upstream has dropped instrumentation-fastify, so we are as well.
The test case has changed to verify that using EDOT Node.js and
the 3rd-party @fastify/otel works.

Refs: open-telemetry/opentelemetry-js-contrib#3409

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

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Run ID: cc0454f2-5afc-4a8a-8ac4-803a9a8f8286

📥 Commits

Reviewing files that changed from the base of the PR and between 452e12b and a40a665.

📒 Files selected for processing (2)

• packages/opentelemetry-node/lib/instrumentations.js
• packages/opentelemetry-node/test/fixtures/telemetry-with-fastify-otel.mjs

✅ Files skipped from review due to trivial changes (1)

• packages/opentelemetry-node/test/fixtures/telemetry-with-fastify-otel.mjs

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/opentelemetry-node/lib/instrumentations.js

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📝 Walkthrough

Walkthrough

This pull request removes built-in Fastify instrumentation from EDOT Node.js by deleting @opentelemetry/instrumentation-fastify from code, types, and dependencies. Documentation and release notes were updated to document the breaking change and migration to the third-party @fastify/otel package, including a new bootstrap fixture (telemetry-with-fastify-otel.mjs). Tests and test fixtures were adjusted to reflect the external instrumentation and updated environment-variable handling. Package scripts and lint checks were updated to account for the new/removed packages.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch trentm-drop-instr-fastify

• 🛠️ Update Documentation: Commit on current branch
• 🛠️ Update Documentation: Create PR

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