chore(module): trim stale PR-I genesis-tag rationale (#381)

[trilamsr]

Summary

module/doc.go carries an 8-line rationale for the module/v0.0.1 genesis tag and PR-I.1a/PR-I.1b/PR-I.2 sequencing. All three PRs landed long ago; the module is alive, well, and resolvable through the Go module proxy.

Root cause

The doc.go was authored when the module-split was an active multi-PR sequence; the proxy-resolution rationale was load-bearing for reviewers verifying the genesis tag cut. Both conditions are now historical. Reading it cold today produces noise, not signal.

Fix

Trim to a 2-line package doc. package module declaration retained — Go module proxy requirement.

Test plan

• go list -m github.com/tracecoreai/tracecore/module → resolves
• golangci-lint, govet, attribute-namespace-check pass (pre-push hook)

Closes #381.

chore: trim stale PR-I genesis-tag rationale from `module/doc.go` — package doc only.

[trilamsr]

Superseded by #392 which bundles #381+#383+#379 in one PR with better scope.