Acknowledge a codex-pair HIGH finding

Records an ack for the given finding hash so the codex-pair Stop-gate skips it on future turn-ends. The gate prints a full 16-char hash in its block message, e.g. [fc69d46835dfd2ab] src/auth.ts — pass that hash verbatim.

Instructions

1. Parse args. The first whitespace-delimited token is <hash> (16-char hex). The remaining text (strip enclosing quotes if present) is <reason>. If either is missing, print usage and stop:

   Usage: /codex-pair-ack <hash> "<reason>"
   Example: /codex-pair-ack fc69d46835dfd2ab "false positive — test-only code path"

1. Locate the `.codex-pair/` directory. Walk up from the current working directory looking for .codex-pair/context.md. The directory that contains .codex-pair/ is <markerDir>. If no marker is found after reaching the filesystem root, tell the user:

   codex-pair is not enabled in this project (no .codex-pair/context.md found). Nothing to acknowledge.

1. Validate the hash before using it: it must match ^[0-9a-f]{16}$. If it does not, print the usage block from step 1 and stop (a malformed hash means the user mistyped it).

1. Record the ack by running the Bash command below. Substitute real values for <plugin-root> (the absolute path of this plugin, i.e. the value of CLAUDE_PLUGIN_ROOT), <markerDir>, and <hash>. Do NOT interpolate `<reason>` into the command string — the reason is read from stdin via a single-quoted heredoc so the shell never expands $(...), backticks, or quotes inside it (injection-safe). Replace the <reason> line with the user's reason text verbatim:

   node --input-type=module -e '
   import { addAck } from "<plugin-root>/scripts/lib/state.mjs";
   import { readFileSync } from "node:fs";
   // With `node -e CODE A B`, process.argv = [node, A, B] (no script-file
   // placeholder), so argv[1]=markerDir, argv[2]=hash.
   addAck(process.argv[1], process.argv[2], { reason: readFileSync(0, "utf8").trim() });
   ' "<markerDir>" "<hash>" <<'CODEX_PAIR_ACK_REASON'
   <reason>
   CODEX_PAIR_ACK_REASON

addAck writes to <markerDir>/.codex-pair/state/acks.json (creating the directory if needed). The hash is passed verbatim — no resolution is performed.

1. Confirm to the user:

   Acknowledged `<hash>` — <reason>. The Stop-gate will skip this finding.

If the node one-liner exits non-zero, surface the error output so the user can diagnose it.