fix(v0.3.1): sated bot stops chasing food + perf-leak + fuzzy improvement dedup

Third day of "bot just walks back and forth burning tokens". Root
causes were mechanical, not the manifesto:

1. SATED BOT CHASING FOOD (the big one)
   Bot had food=17 (nearly full) but storyline first_food + manifesto
   L1 required 2+ food ITEMS in inventory, so it looped scout-food /
   acquire-food for hours instead of working. Now both treat a hunger
   bar >= 14 (SATED_FOOD) as satisfied even with empty food inventory —
   a full bot chops wood / makes tools and grabs food opportunistically,
   only hard-pursuing food when actually hungry (< 14).
   manifesto/needs.js foodDetect + goal/storyline.js first_food.completed.

2. perf_hooks MEMORY LEAK (overnight OOM suspect)
   "MaxPerformanceEntryBufferExceededWarning: 1,000,001 measure entries".
   mineflayer/pathfinder emit perf marks we never consume. Added a
   60s reaper in bot.js (performance.clearMeasures/clearMarks). unref'd.

3. IMPROVEMENT QUEUE SELF-DUPLICATING
   The LLM re-filed closed gaps with reworded titles (#5/#8/#9 were
   dupes of implemented #1/#2/#3). Exact-title dedup missed them.
   Replaced with token-set fuzzy match (isDuplicateTitle): jaccard>=0.75
   OR >=3 shared meaningful tokens with jaccard>=0.5. Also: a re-filed
   gap that's already implemented/rejected is NOT resurrected as a new
   open row. Cleared all 5 open requests (now genuinely implemented).

Also confirmed (no change needed):
- canDig=true is a DELIBERATE codebase-wide choice ("without it the bot
  gets permanently stuck", actions.js). The stale memory recommending
  canDig=false is updated. ViaBackwards dig works partially (dug:1
  moved:1.8 observed); false would trap the bot in every pit.
- scout-food already has blind/tunnel fallback + 12s step timeout
  (operator's earlier edits) so trapped-pathfinder degrades instead of
  hanging 30s.

Tests: 407 green (was 404). Updated needs/state/storyline tests for the
SATED_FOOD threshold; added fuzzy-dedup + tokenize/jaccard tests.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

runtime/knowledge/knowledge.test.js

@@ -320,6 +320,42 @@ test("improvement requests: create, dedup-by-title bumps votes, list filters", a
 	assert.ok(!stillOpen.some((r) => r.id === id1));
 });
 
+test("improvement requests: fuzzy dedup catches reworded titles + won't resurrect closed ones", async () => {
+	await bootstrap();
+	if (!isAvailable()) return;
+	const a = createImprovementRequest({
+		source: "postmortem", category: "skill",
+		title: "Нет навыка целевого поиска еды по биому", priority: 1,
+	});
+	assert.ok(a);
+	// Reworded near-duplicate — should map to the SAME row, bump votes.
+	const b = createImprovementRequest({
+		source: "reflect", category: "skill",
+		title: "Нет навыка целевого дальнего поиска еды по биому", priority: 1,
+	});
+	assert.equal(b, a, "reworded title deduped to original");
+
+	// Mark it implemented, then the LLM re-files the same gap reworded
+	// again — must NOT create a fresh open row (no resurrection).
+	markImprovementStatus(a, { status: "implemented", notes: "scout-food" });
+	const c = createImprovementRequest({
+		source: "reflect", category: "skill",
+		title: "Нужен навык дальнего поиска еды по биому", priority: 1,
+	});
+	assert.equal(c, a, "re-filed closed gap returns existing id, no new row");
+	const open = listImprovements({ status: "open" });
+	assert.ok(!open.some((r) => r.id === a), "closed gap stays closed");
+});
+
+test("tokenize / jaccard: similarity helpers", async () => {
+	const { tokenize, jaccard } = (await import("./index.js")).__testing;
+	const t1 = tokenize("Нет навыка целевого поиска еды по биому");
+	const t2 = tokenize("Нет навыка целевого дальнего поиска еды по биому");
+	assert.ok(jaccard(t1, t2) >= 0.6, `expected ≥0.6, got ${jaccard(t1, t2)}`);
+	const t3 = tokenize("Trigger wedged_96s has low success rate");
+	assert.ok(jaccard(t1, t3) < 0.3, "unrelated titles score low");
+});
+
 test("improvement requests: priority and status ordering", async () => {
 	await bootstrap();
 	if (!isAvailable()) return;