The frozen squash-merge body and pull-request.sh are removed #884

Problem

After child 20 nothing reaches the frozen body of squash-merge.sh (254 code lines) or pull-request.sh (107 code lines), the helper the frozen merge scripts used for pull request reading. Both live in packages/agents/source/skills/merge-pr/shared/scripts/.

This child removes only non-owner shell. pull-request.sh ends by loading merge-agent.sh, and merge-agent.sh and merge-policy.py match owner_paths and constitutional_paths in .agents/agent-skills.conf at origin/main, so deleting those two (with their generated copies) belongs to the single cutover issue under #588, which depends on this child. merge-agent.sh does not load pull-request.sh, so removing the helper first leaves only unreachable owner-path code behind.

Part of #324, within #588. Child 23 in #324's Children list. Removes the frozen squash-merge.sh body and pull-request.sh, with their generated copies.

Acceptance criteria

1. AC1: Given the sources, packages and deployments, when a search for pull-request.sh or the frozen squash-merge.sh body runs after this change, then none remains in the source, both harness packages and both deployments; the squash-merge.sh and merge.sh wrappers of child 26 still exist and work.
2. AC2: Given the complete regeneration sequence of mise.toml (regen-generated, followed by check-generated-skills), when it runs, then output is current, tokens.json is re-measured, the deployments and apm.lock.yaml are refreshed and the check passes.
3. AC3: Given the documentation, when it mentions pull-request.sh or the removed body, then it is updated, and a reference search over the documentation shows no obsolete guidance.
4. AC4: Given the merge path, when CI runs on macOS, Linux and Windows, then it passes with the frozen shell absent.
5. AC5: Non-functional: no wrapper, production script, Go test or Bats case references a removed file, no reference to pull-request.sh remains, and this change edits no path matched by constitutional_paths or owner_paths in .agents/agent-skills.conf.

Scope and non-goals

Scope: the deletion of the frozen squash-merge.sh body and pull-request.sh, regenerated output and documentation.

Non-goal: changing Go behavior. Non-goal: deleting merge-agent.sh, merge-policy.py, lib.sh or any other owner-tier or constitutional path, which the cutover issue under #588 does. Non-goal: the five other frozen bodies (child 22).

Approach

Meet AC1 to AC5 in one deletion with regenerated output. Mechanism is the implementer's choice.

Dependencies

Blocked by: #882, #883, #875, #333.

Child 22 must merge first: the frozen preflight.sh, review.sh and lint-squash-msg.sh bodies it removes still load pull-request.sh. The cutover issue under #588 (not a child of this split) follows this child.

Prerequisites: #333.

Size

S. One pull request. 361 code lines deleted from source at origin/main (a physical-line code count), under 800 with documentation. Only generated output under packages/agents/claude/.apm/skills/, packages/agents/codex/.apm/skills/, .claude/skills/, .agents/skills/ and tokens.json is excluded from the count; the source copy always counts.

Verify plan

• AC1: the search output over source, packages and deployments.
• AC2: mise run regen-generated then mise run check-generated-skills, with the tokens, deployments and lock diff cited.
• AC3: the lint-prose and Markdown gates and a documentation reference search.
• AC4: the CI matrix run.
• AC5: a search of the tests and of every production script for the removed names (the former callers in preflight.sh, review.sh and lint-squash-msg.sh included), and the protected-path scan output on the pull request's file list.
• Definition of done: D1 each AC is verified at the merged head, with the commands and results cited in the pull request's Verification. D2 an independent review approves the exact merged head, and every finding has a recorded disposition. D3 required checks pass with no gate loosened. D4 the leak scans the repository specifies are clean, and every post made for this work passes the per-post leak review before it is posted. D5 every commit is signed. D6 the documentation matches the change or the Verification says why there is no impact. D7 every commit has an Assisted-by trailer and the pull request has the provenance:agent-assisted label. D8 the pull request stays within the size limits. D9 follow-ups are filed as issues and listed under Related. D10 the merge closes the issue through a closing reference, the board shows Done, and the final Status: comment names the merge commit.

Risks

Another script that loads these files would break; AC1 and AC5 search for loaders. Undo: revert; the files return.

Operator authority

None. No path matched by constitutional_paths or owner_paths is touched (AC5).