## What
A population ratchet over **legacy-id collections consulted against a
live column value** (`SOME_SET.has(task.column)`), recorded as 23 sites.
## Why
The census scans `===`/`!==` comparisons. A Set or array literal is a
**definition**, so no census run has ever pointed at one. Three
found-by-hand defects came from that blind spot:
| collection | symptom |
|---|---|
| `GITHUB_TRACKING_EDITABLE_COLUMNS` | operator could not toggle GitHub
tracking **at all** on a renamed board — no error, affordance absent
(#3149) |
| `TIME_INDICATOR_COLUMNS` | wrong elapsed-time indicator on cards |
| `BLOCKER_ESCALATION_COLUMNS` | escalation skipped renamed lanes |
#3149 enumerated the population by hand and concluded *"this is where
the remaining renamed-board defects actually live."* A number in a PR
body rots. This is that enumeration as a ratchet.
## Census
**Unchanged — `AVAILABLE: 0` before and after, 12 documented deferrals
both sides.** This PR converts nothing. It ratchets a class the census
*structurally cannot see*, which is the point: the backlog reading zero
has never meant the lane vocabulary is fully converted, only that the
measurable part is. Recording that plainly instead of claiming a delta
this change does not produce.
## What it claims, and what it deliberately does not
It claims the **population** is the recorded set. It does **not** claim
each site is correct — 20 of the 23 are #3149's assessment ("most are
already correct, either no-flags fallbacks or seed-then-add resolved
sets"), and I did not re-verify them. Blessing sites I have not read is
how a ledger becomes a list of things someone once glanced at. A new
entry fails the test and a human reads that **one** site; that is the
entire mechanism.
## My own detector's pick-work list was 100% false positives
Measured, and the reason this ships with **no candidate list**. The
heuristic "no role-helper call in the file" flagged three sites; all
three were fine:
- `agent-role-policy.ts:32` — a documented **FLAGGED, NOT FIXED**
deferral with its reasoning recorded
- `DocumentsView.tsx:88` — already converted, flags-first; the flags
arrive as a threaded **object**, so a scan for resolver *calls* cannot
see the conversion
- `agent-assignment.ts:118` — a `DELIBERATE-LITERAL` fallback behind an
injected `countsAsAssignmentLoad` callback, reviewed `2026-07-31-05:40`
That is the same failure `--triage`'s pick-work list had before #3194
fixed it, from the same cause: **inferring "unexamined" from the absence
of a pattern rather than from evidence.** A detector that cannot
distinguish "not yet looked at" from "looked at and settled" must not be
pointed at a work queue. It can still hold a population steady, which is
all this does.
## Verification
Mutation-verified in **both** directions — a ledger fails by missing
additions *or* by keeping ghosts:
```
### baseline Tests 4 passed (4)
### MUTATION 1 — new unrecorded gating collection
+ "packages/engine/src/worktree-pool.ts :: NEW_LANE_GATE",
Tests 1 failed | 3 passed (4)
### MUTATION 2 — recorded site vanishes (ghost)
+ "packages/engine/src/worktree-pool.ts :: managedRenamed",
+ "packages/engine/src/worktree-pool.ts :: managed",
Tests 2 failed | 2 passed (4)
### restored Tests 4 passed (4)
```
Two anti-vacuity cases guard the detector: it still finds the
collections whose defects motivated the file, and it does **not** claim
plain comparisons (asserted against `self-healing.ts`, dense with column
comparisons and no gating collection) — pulling those in would
double-count a class that already has a gate.
## Flagged, not guessed
- **Line numbers are excluded** from ledger entries — they drift with
unrelated edits and would fail this test for reasons that are not about
lane vocabulary.
- **Comments stripped before scanning:** `TaskDetailModal.tsx` and
`TaskCard.tsx` both quote their own collection by name in FNXC notes
explaining the bug it caused. Counting prose would fire the ledger on
the files that document the hazard most carefully.
- **Stated reach limits** (in-file): only *named* collections consulted
as `.has`/`.includes`; the argument must mention column/lane;
property-reached collections are missed. A miss is a site nobody is
watching — not a false green on a listed site.
No changeset: test-only, behavior-preserving, no published-package
surface.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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