feat(runtime): stuck-incident detector + skill metrics + edit scope (Phase 6) (#17)

Phase 6 of plans/autonomous-survival-bot-prd.md. Expand the
self-improvement loop so the bot can spot and report no-progress
stagnation, not just exception-class failures.

New:
- runtime/stuck-incident.js: detector fires a structured proposal when
  the same noProgressReason persists past 5 min (cooldown 30 min).
  Body includes runtimeState, milestone, suggested skill, slim
  snapshot, last action result, per-skill success/failure metrics
  and a forbidden-paths list. Pure module — caller (bot.js) writes
  the proposal.
- runtime/skill-metrics.js: in-memory per-skill ok/fail counters
  surfaced on snapshot.skillMetrics for the TUI and the incident
  body.
- runtime/stuck-incident.test.js: 6 tests covering null reason,
  threshold gating, cooldown, reason change resetting the timer,
  body composition and metrics snapshot.

Wiring:
- runtime/state-store.js: writeProposal accepts {editScope: string[]}
  and persists it in the frontmatter; readProposalEditScope() reads
  it back so future auto-patch.js can refuse cherry-picks that touch
  other areas.
- runtime/bot.js: tick() invokes the stuck detector each tick,
  records skill ok/fail via skillMetrics, stamps snapshot.skillMetrics
  and writes the stuck proposal via writeProposal({editScope}).
  dispatchAction now records into skillMetrics for both the
  resolved-result and the exception path.

npm test now 46/46.

Co-authored-by: Yuriy Mayatnikov <mayatnikov@me.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

runtime/state-store.js

@@ -134,25 +134,49 @@ function slugify(s) {
 		.slice(0, 60);
 }
 
-export function writeProposal({ kind, summary, body }) {
+// editScope (optional): array of repo-relative path prefixes the
+// auto-patcher is allowed to modify. Read back from the frontmatter
+// so scripts/auto-patch.js can refuse cherry-picks that touch other
+// areas. Falls back to the historical default (`runtime/`) when
+// absent for backwards compatibility with older proposals.
+export function writeProposal({ kind, summary, body, editScope }) {
 	const stamp = new Date().toISOString().replace(/[:.]/g, "-").slice(0, 19);
 	const filename = `${stamp}-${slugify(kind)}.md`;
 	const filePath = path.join(PROPOSALS_DIR, filename);
-	const content = [
+	const frontmatter = [
 		"---",
 		`kind: ${kind}`,
 		`ts: ${new Date().toISOString()}`,
 		`summary: ${JSON.stringify(summary)}`,
 		"approved: false",
-		"---",
-		"",
-		body,
-		"",
-	].join("\n");
+	];
+	if (Array.isArray(editScope) && editScope.length) {
+		frontmatter.push(`editScope: ${JSON.stringify(editScope)}`);
+	}
+	frontmatter.push("---", "");
+	const content = frontmatter.concat([body, ""]).join("\n");
 	fs.writeFileSync(filePath, content);
 	return { filePath, filename };
 }
 
+// Best-effort parse of editScope from a proposal markdown body's
+// frontmatter. Returns null when not specified.
+export function readProposalEditScope(filename, { approved = false } = {}) {
+	const dir = approved ? PROPOSALS_APPROVED_DIR : PROPOSALS_DIR;
+	const filePath = path.join(dir, filename);
+	let raw;
+	try { raw = fs.readFileSync(filePath, "utf8"); } catch { return null; }
+	const m = raw.match(/^---\n([\s\S]*?)\n---/);
+	if (!m) return null;
+	const scopeLine = m[1].split("\n").find((l) => l.startsWith("editScope:"));
+	if (!scopeLine) return null;
+	try {
+		return JSON.parse(scopeLine.slice("editScope:".length).trim());
+	} catch {
+		return null;
+	}
+}
+
 export function listProposals({ approved = false } = {}) {
 	const dir = approved ? PROPOSALS_APPROVED_DIR : PROPOSALS_DIR;
 	try {