Bind authored independent checks to nested-worker pre-claim viability #713

Trigger

An authored nested-parent plan assigns two terminal Workers to src/identifier.py and src/duration.py, with fixed independent checks in checks/check_identifier.py and checks/check_duration.py. The check harness loads modules through importlib.util. The acquired repository map and semantic risk report contain no recognized test dependency edges, so deterministic pre-claim viability parks the parent with clear_verification_path=unknown before any claim or provider dispatch. Renaming the checks to tests/test_*.py alone still leaves no dependency edges; adding static imports makes the current heuristic pass. This was observed with zero Worker launches and zero provider tokens.

Desired behavior

Allow an authored nested plan to declare exact independent verification paths and commands as typed, immutable pre-claim evidence, bound to each Worker assignment and the parent union. Admit only after verifying the checks are existing Git-visible regular files outside Worker write scopes, the commands and paths match the frozen plan, and the repository snapshot and risk inputs remain current. A Worker report or arbitrary task prose must not mint this authority. Preserve fail-closed behavior for missing, modified, unrelated, or unexecutable checks and for tampered plan metadata.

Acceptance

• A parent plus two disjoint Workers with independent checks/check_*.py commands reaches pre-claim without relying on test filename or static-import heuristics.
• Changing a check file, command, assigned path, plan binding, or snapshot after validation refuses before claim/provider dispatch.
• Existing recognized-test and licensed-breakage contracts retain their current behavior; no broad shell or generic self-attestation is added.
• Add deterministic positive and negative tests for the acquired-evidence path, separate from synthetic/fake simulation.

Related: #627. The current qualification fixture can use the minimal static-import/test-path correction while this general contract is designed.