The residual Bats cases for the resolver and readiness groups are retired #933

Problem

After the early cleanup (the first child) and the ports it waits for, some cases in tests/skills/source/lib/ remain only because they exercised shell behavior that a later port now replaces. This issue retires the first allocated group: all of tests/skills/source/lib/gates.bats (129 lines, 10 cases) and tests/skills/source/lib/masked-status.bats (211 lines, 19 cases), plus the cases of tests/skills/source/lib/lib.bats from its start through the worktree readiness cases (lines 1 to 259 at baseline fd7b680: the resolver cases from line 86, the harness and session cases, and the readiness cases). The second group (the remaining lib.bats cases from line 260) is the next child. The group is at most 599 lines at the baseline, below both limits whatever the earlier cleanup removed.

Part of #588 and #321. Deletes test cases only; no shell under packages/agents/source/lib/ changes.

Acceptance criteria

1. AC1: Given every case in the allocated group left after the early cleanup, when the extended retirement ledger is read, then each case names the Go test that covers it, or the reason it is dropped, or the reason it needs a real shell, and no case is unaccounted for.
2. AC2: Given the merged change, then every case marked deleted is absent, and what remains of the allocated files is listed with a reason for each case.
3. AC3: Given the ledger, when it is read, then each covering test is marked native or shell-integration, with the platforms on which it executes and does not skip, and CI shows each executing on those platforms.
4. AC4: Given the shell under packages/agents/source/lib/ and the generated skills, then neither changes, and mise run check-generated-skills passes.
5. AC5: Non-functional: the pull request stays below 800 lines of code and 2,000 prose lines, and no coverage of still-shipped shell behavior is lost.

Scope and non-goals

Scope: extending the retirement ledger for the allocated group and deleting its residual duplicate cases.

Non-goal: the remaining lib.bats cases from line 260 (the next child). Non-goal: deleting any shell, the capability probe or the fallback. Non-goal: porting any further behavior. Non-goal: the transaction ports #322 to #327.

Approach

Meet AC1 to AC5. Extend the ledger from the case names still present in the allocated group, then delete. The mechanism is the implementer's choice within those outcomes.

Dependencies

Blocked by: #927 (the early Bats cleanup), #928 (the locale child), #932 (the binary resolver and configuration bridge child), #755 (context and harness), #713, #770, #762 (confirmation and delegation cases at tests/skills/source/lib/masked-status.bats:70 and tests/skills/source/lib/masked-status.bats:76), #771 (reviewer execution case at tests/skills/source/lib/masked-status.bats:117), #851 (child 02 of #322, which owns the worktree readiness cases beginning at tests/skills/source/lib/lib.bats:185; the readiness scope still published on #755 and #772 is superseded by that assignment and is not reopened here), #753 (golden-file protection for the Go enforcement paths).

A case whose prerequisite has not landed is kept in the ledger with the later retirement owner named, not deleted.

Size

S. One pull request, deletions only, with an allocation of at most 599 lines at the baseline.

Verify plan

• AC1: a check that lists the case names in the allocated group and compares each with the ledger.
• AC2: git diff shows only deletions of ledger-marked cases, and the Bats run for the remaining suites passes.
• AC3: the ledger columns checked by a script, and the CI job logs for the named Go tests on each promised platform.
• AC4: git diff --stat shows no file outside tests/skills/source/lib/ and the ledger, and mise run check-generated-skills passes.
• AC5: the pull request's size report and the ledger coverage comparison.
• 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

Deleting a case whose Go equivalent is weaker loses coverage; the ledger names each covering test and the review checks it. Undo: revert the change, which restores the cases.

Operator authority

None.