test(sf): lock escalation→memory persistence contract

Commit 00c13bc5a added "createMemory on resolveEscalation" but the
behavior was untested — a regression that broke it would silently
disable the cross-session learning surface (the [escalation:T##]
memories are what carry agent rationales forward via getRelevantMemories
ranking).

Two new tests:
1. resolveEscalation with explicit user rationale → memory contains
   the question, choice, and user rationale, category=architecture.
2. resolveEscalation with empty rationale → falls back to the
   artifact's recommendationRationale (the formatEscalationMemoryContent
   contract).

23 tests in the file now (was 21).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/resources/extensions/sf/tests/escalation-feature.test.ts

@@ -298,4 +298,54 @@ describe("claimOverrideForInjection (carry-forward)", () => {
 		assert.equal(after?.escalation_awaiting_review, 0);
 		assert.equal(after?.escalation_artifact_path, before);
 	});
+
+	test("resolveEscalation persists choice + rationale as a memory", async () => {
+		writeEscalationArtifact(dir, buildEscalationArtifact(baseArtifact));
+		const result = resolveEscalation(
+			dir,
+			"M001",
+			"S01",
+			"T01",
+			"fail",
+			"explicit user rationale here",
+		);
+		assert.equal(result.status, "resolved");
+		const { getActiveMemories } = await import("../memory-store.ts");
+		const memories = getActiveMemories();
+		assert.ok(
+			memories.length >= 1,
+			`expected at least 1 memory, got ${memories.length}`,
+		);
+		const escalationMemory = memories.find((m) =>
+			m.content.startsWith("[escalation:T01]"),
+		);
+		assert.ok(escalationMemory, "no [escalation:T01] memory was written");
+		assert.equal(escalationMemory!.category, "architecture");
+		assert.match(escalationMemory!.content, /Overwrite or fail\?/);
+		assert.match(escalationMemory!.content, /Chose:/);
+		assert.match(escalationMemory!.content, /explicit user rationale here/);
+	});
+
+	test("auto-mode resolveEscalation falls back to recommendationRationale when no user rationale", async () => {
+		writeEscalationArtifact(dir, buildEscalationArtifact(baseArtifact));
+		resolveEscalation(
+			dir,
+			"M001",
+			"S01",
+			"T01",
+			"accept",
+			"", // empty rationale — should fall back to art.recommendationRationale
+		);
+		const { getActiveMemories } = await import("../memory-store.ts");
+		const memories = getActiveMemories();
+		const escalationMemory = memories.find((m) =>
+			m.content.startsWith("[escalation:T01]"),
+		);
+		assert.ok(escalationMemory);
+		assert.match(
+			escalationMemory!.content,
+			/data loss is irreversible/,
+			"empty user rationale should fall back to recommendationRationale",
+		);
+	});
 });