`[2026-09-26]` Greedy exact-match as parity for a small generative seat (coder)

Greedy exact-match as parity for a small generative seat (coder) — same-host repeats matched only 30–38% (run B hit the prefix cache, so a different numeric path; near-tie tokens cascade). Use teacher-forced logprobs of real text with cache_salt: each host bit-exact with itself. stacks/coder-seat/README.md.