fix: harden the org-file mutators and close four verified bugs

An overnight hygiene run over this repo, reviewed adversarially afterward. Every problem below was reproduced before it was fixed, and every fix was re-checked by a skeptic who was told to refute it.

cj-remove-block could silently destroy content. Its range check validated only the first and last lines, so a span from one cj block's opener to a later block's closer passed and the removal deleted everything between — prose, headings, whole tasks, with a zero exit. That is the failure the check exists to prevent, and drift is its normal case, since the calling skill edits the file while processing. It now refuses a range holding more than one block, backs up first, and writes atomically while preserving the file's mode and following symlinks to the real target.

todo-cleanup rewrote todo.org with no backup, alone among the three tools that mutate these files. It now copies to the temp dir like lint-org does. Both backup helpers suffix rather than overwrite, because a second-resolution stamp collapsed two back-to-back invocations into one backup holding already-mutated content — and running todo-cleanup twice in a row is the shipped path.

audit.bats failed about one run in eight, in teardown rather than in its assertions, so a passing test reported as a false red. git commit spawns a detached maintenance process that is still writing packs when the commit returns, racing the cleanup. The fixture disables it.

route_recommend downgraded a correct strong match to weak when two projects shared a basename. lint.sh now sweeps the scripts that get symlinked onto PATH, which were the only shell in the repo with no gate over them.

Two test defects found in review and fixed here: a suite that deleted real backups from the shared temp dir, and one that depended on that directory's contents. Isolation now lives in an autouse fixture rather than in each test's memory.

Known and filed, not closed: the range check still cannot prove the range is the block that was scanned, so drift by exactly one whole block deletes the wrong annotation. That needs a content assertion and a CLI contract change.

1 files changed, 28 insertions, 0 deletions

diff --git a/.ai/scripts/tests/test_route_recommend.py b/.ai/scripts/tests/test_route_recommend.py
index acc4755..2ec900a 100644
--- a/.ai/scripts/tests/test_route_recommend.py
+++ b/.ai/scripts/tests/test_route_recommend.py
@@ -122,3 +122,31 @@ def test_cli_exclude_drops_current_project(tmp_path):
     r = _run(["--exclude", "foo"], roots=[tmp_path / "projects"], item="fix the foo widget")
     assert r.returncode == 0
     assert r.stdout.strip() == "none"
+
+
+# ----------------------------------------------------------------------
+# Duplicate candidate names
+#
+# Projects are collapsed to bare basenames, so two projects sharing a basename
+# across roots (~/code/notes and ~/projects/notes) appear twice in the candidate
+# list. Both literal-match, recommend read len(strong) > 1 as an ambiguous tie,
+# and a correct strong match was downgraded to weak. Latent when discovered
+# 2026-07-24 (27 projects, 27 distinct basenames) but real.
+# ----------------------------------------------------------------------
+
+def test_duplicate_candidate_name_keeps_strong_confidence():
+    assert rr.recommend("fix the notes thing", ["notes", "other"]) == ("notes", "strong")
+    # The same name twice must not read as a tie.
+    assert rr.recommend("fix the notes thing", ["notes", "notes", "other"]) == ("notes", "strong")
+
+
+def test_genuine_ambiguity_still_downgrades():
+    # Two DIFFERENT projects both matching is a real tie and stays weak — the
+    # dedupe must collapse identical names only, never real ambiguity.
+    dest, conf = rr.recommend("notes and other both", ["notes", "other"])
+    assert conf == "weak"
+
+
+def test_duplicates_do_not_change_the_chosen_destination():
+    dest, _ = rr.recommend("fix the notes thing", ["notes", "notes"])
+    assert dest == "notes"