Select the provider-neutral backend and port repo-owned commit-msg
and test-harness refs into `.ai`.
Also,
- ignore local `.agents` links and generated runtime state.
- retain legacy Claude archives for recovery.
- record Prompt-IO provenance for the migration.
Prompt-IO: ai/prompt-io/opencode/20260907T214000Z_0c52f27_prompt_io.md
(this patch was generated in some part by `opencode` using `gpt-5.6-sol` (`openai`))
Gud Boi