feat(FN-4080): complete Step 1 — add thinking persistence resolver

Fusion-Task-Id: FN-4080
Fusion-Task-Lineage: 086863ba-7100-41ab-9cfc-197301fbcab0

packages/core/src/__tests__/resolvePersistAgentThinkingLog.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it } from "vitest";
+import { resolvePersistAgentThinkingLog } from "../types.js";
+
+describe("resolvePersistAgentThinkingLog", () => {
+  it("returns false for both kinds when granular and legacy are unset", () => {
+    expect(resolvePersistAgentThinkingLog({}, { ephemeral: false })).toBe(false);
+    expect(resolvePersistAgentThinkingLog({}, { ephemeral: true })).toBe(false);
+  });
+
+  it("uses granular permanent setting when defined", () => {
+    expect(
+      resolvePersistAgentThinkingLog(
+        { persistAgentThinkingLogPermanent: true, persistAgentThinkingLogEphemeral: undefined },
+        { ephemeral: false },
+      ),
+    ).toBe(true);
+    expect(
+      resolvePersistAgentThinkingLog(
+        { persistAgentThinkingLogPermanent: true, persistAgentThinkingLogEphemeral: undefined },
+        { ephemeral: true },
+      ),
+    ).toBe(false);
+  });
+
+  it("falls back to legacy setting when granular fields are undefined", () => {
+    expect(resolvePersistAgentThinkingLog({ persistAgentThinkingLog: true }, { ephemeral: false })).toBe(true);
+    expect(resolvePersistAgentThinkingLog({ persistAgentThinkingLog: true }, { ephemeral: true })).toBe(true);
+  });
+
+  it("prioritizes granular setting over legacy fallback", () => {
+    expect(
+      resolvePersistAgentThinkingLog(
+        { persistAgentThinkingLogPermanent: false, persistAgentThinkingLog: true },
+        { ephemeral: false },
+      ),
+    ).toBe(false);
+    expect(
+      resolvePersistAgentThinkingLog(
+        { persistAgentThinkingLogEphemeral: false, persistAgentThinkingLog: true },
+        { ephemeral: true },
+      ),
+    ).toBe(false);
+  });
+});

packages/core/src/__tests__/settings-parity.test.ts

@@ -62,11 +62,19 @@ describe("settings key parity", () => {
     expect(isGlobalSettingsKey("persistAgentThinkingLog")).toBe(true);
     expect(isProjectSettingsKey("persistAgentThinkingLog")).toBe(false);
     expect(isGlobalOnlySettingsKey("persistAgentThinkingLog")).toBe(true);
+    expect(isGlobalSettingsKey("persistAgentThinkingLogPermanent")).toBe(true);
+    expect(isProjectSettingsKey("persistAgentThinkingLogPermanent")).toBe(false);
+    expect(isGlobalOnlySettingsKey("persistAgentThinkingLogPermanent")).toBe(true);
+    expect(isGlobalSettingsKey("persistAgentThinkingLogEphemeral")).toBe(true);
+    expect(isProjectSettingsKey("persistAgentThinkingLogEphemeral")).toBe(false);
+    expect(isGlobalOnlySettingsKey("persistAgentThinkingLogEphemeral")).toBe(true);
     expect(isGlobalSettingsKey("researchSettings")).toBe(false);
   });
 
   it("defaults persisted thinking logs to disabled", () => {
     expect(DEFAULT_GLOBAL_SETTINGS.persistAgentThinkingLog).toBe(false);
+    expect(DEFAULT_GLOBAL_SETTINGS.persistAgentThinkingLogPermanent).toBe(false);
+    expect(DEFAULT_GLOBAL_SETTINGS.persistAgentThinkingLogEphemeral).toBe(false);
   });
 
   it("includes heartbeatMultiplier in project defaults", () => {