docs(microvm): explain image and runtime dependencies

[edersonbrilhante]

Description

Documents the deployment dependencies for Lambda MicroVM runners after #5280.

• Distinguishes the MicroVM image build role from the runner execution role.
• Explains that the build role creates and publishes the image, while the execution role is passed by the control-plane TypeScript to RunMicrovm and runs the ephemeral job.
• Documents the dependency order: apply the MicroVM foundation, build and release the lifecycle-hook server, build the image with Packer, and deploy the runner control plane.
• Points to the repository examples for the foundation, image, lifecycle-hook, and combined EC2/MicroVM webhook deployment.
• Documents that the lifecycle-hook server is built and released through the existing Lambda artifact workflow, then embedded in the MicroVM image.

Test Plan

• Ran git diff --check.
• Reviewed the documented role ownership and commands against the foundation, MicroVM provider, image, lifecycle-hook, and multi-runner example implementations.
• Confirmed the change is documentation-only; no infrastructure was deployed.

Related Issues

• Stacked on feat(microvm): add lifecycle hook service #5280.
• Related foundation work: feat(microvm): add microvm example #5377.
• Related MicroVM provider work: feat(microvm): add Terraform provider #5413 and feat(compute-providers): add Lambda MicroVM provider #5255.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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