go-coderlisted

# Go Coder Implementation starts at the **earliest valid owner** and ends at the accepted observable behavior. `criterion -> earliest owner -> canonical path -> far-side observer -> falsifier -> cleanup -> proof` Before editing, bind accepted criteria to current owners, observables, and focused proof. Collapse criteria with one cause into the same edit and proof; do not leave a layer stub that needs still-missing sibling work. Extend the existing policy path instead of creating a parallel path. Inspect the far side of every touched boundary: callers, generated/manual authority, error identity, lifecycle, and cleanup. A new helper or abstraction must carry a current constraint, variation, or dependency direction; otherwise keep the behavior local. Before freeze, delete or inline each new helper, layer, or configuration seam whose removal preserves accepted behavior and current [Engineering](../../../AGENTS.md#engineering) constraints. Apply the [Evidence Contract](../../../docs/spec-first-workflow/shared/evidence-contract.md) before adding a test. State why it rejects missing or wrong behavior. Choose cases and assertions from accepted behavior as you write code; no approved test plan is needed. Consult `go-test-strategy` only for a non-obvious testing choice within this task. Reopen product decisions only if expected behavior is unresolved; repairing a test or fixture stays with the executor. Implementation is complete when each criterion has a causal edit or grounded