electron+tests: zoom plumbing (construction-only lights), hermeticity fence for the jobs suite

- ZOOM: the ⌘±/⌘0 ladder is owned, not stock roles — applyZoom sets the
  factor and broadcasts 'lh:zoom'; the renderer publishes --lh-zoom; the
  gutter lengths (.lh-lights-gutter / .lh-closed-toggle) divide by it so
  their RENDERED size is a physical constant at every zoom — the graph
  button stays glued next to the lights, nothing slides under them.
  before-input-event catches ⌘=/layout variants the menu's Plus may not
  claim; did-finish-load re-pushes on reload; getZoom covers first paint.
  The lights themselves stay at construction position — Electron 44 has
  NO setTrafficLightPosition (options-only; the first run crashed on
  it). HIG-acceptable: native lights hug the corner; the web chrome
  compensates around them.
- JOBS SUITE FLAKE, actually fixed this time: the seams are
  module-global and the sweep scans every record — a timed-out async
  test left a running orphan + late wake that poisoned its NEIGHBORS
  (respawned 3 !== 0). New afterEach fence: settle every tracked
  running job, unregister aborts, seams reset to inert no-ops — every
  test starts from identical state regardless of upstream flake.
  Verified: two consecutive full-suite runs 1326/1326.

tests/jobs.test.ts

@@ -26,7 +26,7 @@
 import assert from "node:assert/strict";
 import * as fs from "node:fs";
 import * as path from "node:path";
-import { after, describe, it } from "node:test";
+import { after, afterEach, describe, it } from "node:test";
 import { createFauxCore, fauxAssistantMessage, fauxText, fauxToolCall, type AssistantMessage, type FauxResponseStep } from "@earendil-works/pi-ai";
 import {
 	accumulateJobUsage,
@@ -123,6 +123,33 @@ function trackJob(id: string) {
 	createdJobs.push(id);
 }
 
+/* THE HERMETICITY FENCE (owner round 7, 2026-10-05): the jobs seams are
+ * MODULE-GLOBAL (setJobRespawn / setTurnRunner / the abort registry) and
+ * the sweep scans EVERY job in the store. An async test that times out
+ * under full-suite load leaves a "running" record and a late wake behind
+ * — and that stray state then poisons the NEXT test (a foreign respawn
+ * lands in its counter; a foreign orphan in its sweep). Under isolation
+ * nothing ever times out, which is why the file passes alone and flaked
+ * in the full run. The fence makes every test's start state identical:
+ * all tracked jobs settled, aborts unregistered, seams inert. */
+afterEach(() => {
+	for (const id of createdJobs) {
+		try {
+			const job = jobStore.getJob(id);
+			if (job && job.status === "running") {
+				jobStore.updateJob(id, { status: "done", activity: "settled (fence)" });
+			}
+			unregisterJobAbort(id);
+		} catch {
+			/* already gone */
+		}
+	}
+	// Late wakes from a prior test must be inert: a no-op respawn can't
+	// increment anyone's counter, a no-op runner can't spawn real work.
+	setJobRespawn(() => {});
+	setTurnRunner(async () => 200);
+});
+
 after(() => {
 	for (const id of createdChats) {
 		try {