collection/rpc: convert RPC engine to component.Component

[devin-ai-integration]

collection/rpc: convert RPC engine to component.Component

Summary

• Replace legacy engine.Unit lifecycle with component.Component managed by ComponentManager.
• Add workers:
  • serveGRPCWorker: bind listen address, signal ready after successful bind, then grpc.Serve.
  • shutdownWorker: wait for shutdown and call GracefulStop.
• Preserve existing API registration, metrics, interceptors, and rate limiting.
• No changes to error messages unless necessary.

Readiness semantics

• Ready is signaled only after binding to the listen address succeeds, matching patterns used in other engines.

Links and attribution

• Link to Devin run: https://app.devin.ai/sessions/591b16f6b18345ce8bcb61bc8a07c398
• Requested by: Peter Argue (@peterargue)

Verification

• make lint passed locally.
• go build ./... succeeded.

Notes

• Engine now implements component.Component and remains compatible with module.ReadyDoneAware-based builders.

[devin-ai-integration]

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 18 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
engine/collection/rpc/engine.go	0.00%	18 Missing ⚠️

📢 Thoughts on this report? Let us know!

[peterargue]

Suggested change

	e.log.Err(err).Msg("failed to start server")
	ctx.Throw(err)
	ctx.Throw(fmt.Errorf("failed to start server: %w", err))

[peterargue]

Suggested change

	e.log.Error().Err(err).Msg("fatal error in server")
	ctx.Throw(err)
	ctx.Throw(fmt.Errorf("error encountered while running grpc server: %w", err))