feat(FN-3175): document global tool output persistence setting in settings

Added documentation for the global tool output persistence setting to the settings reference guide.

Fusion-Task-Id: FN-3175

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

@@ -55,6 +55,8 @@ describe("settings key parity", () => {
     expect(isGlobalSettingsKey("researchGlobalDefaults")).toBe(true);
     expect(isProjectSettingsKey("themeMode")).toBe(false);
     expect(isGlobalSettingsKey("remoteAccess")).toBe(true);
+    expect(isGlobalSettingsKey("persistAgentToolOutput")).toBe(true);
+    expect(isProjectSettingsKey("persistAgentToolOutput")).toBe(false);
     expect(isGlobalSettingsKey("researchSettings")).toBe(false);
   });
 

packages/core/src/settings-schema.ts

@@ -67,6 +67,8 @@ export const DEFAULT_GLOBAL_SETTINGS = {
   // Dashboard TUI memory guard
   vitestAutoKillEnabled: true,
   vitestKillThresholdPct: 90,
+  // Agent log persistence controls
+  persistAgentToolOutput: true,
   researchGlobalDefaults: {
     searchProvider: undefined,
     synthesisProvider: undefined,

packages/core/src/types.ts

@@ -1441,6 +1441,11 @@ export interface GlobalSettings {
    *  triggers a vitest auto-kill. Clamped to [50, 99] in the UI.
    *  Default: 90. */
   vitestKillThresholdPct?: number;
+  /** When true (default), persist detailed tool argument/result payloads in
+   *  task agent logs (`agent.log`) for `tool`, `tool_result`, and
+   *  `tool_error` entries. When false, tool timeline rows are still stored,
+   *  but their verbose `detail` payload is omitted to reduce log size/noise. */
+  persistAgentToolOutput?: boolean;
   /** Research defaults shared across all projects.
    * Project settings may override these via `researchSettings`. */
   researchGlobalDefaults?: ResearchGlobalDefaults;