feat(FN-3195): document llama.cpp provider setup and onboarding

Docs(FN-3195): adds llama.cpp provider setup and onboarding documentation to the main and dashboard READMEs.

Fusion-Task-Id: FN-3195

packages/core/src/__tests__/use-llama-cpp-settings.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from "vitest";
+import type { GlobalSettings } from "../types.js";
+import {
+  DEFAULT_GLOBAL_SETTINGS,
+  GLOBAL_SETTINGS_KEYS,
+  isGlobalSettingsKey,
+} from "../settings-schema.js";
+
+describe("useLlamaCpp global setting", () => {
+  it("is included in GLOBAL_SETTINGS_KEYS", () => {
+    expect(GLOBAL_SETTINGS_KEYS).toContain("useLlamaCpp");
+  });
+
+  it("defaults to undefined", () => {
+    expect(DEFAULT_GLOBAL_SETTINGS.useLlamaCpp).toBeUndefined();
+  });
+
+  it("is recognized by isGlobalSettingsKey", () => {
+    expect(isGlobalSettingsKey("useLlamaCpp")).toBe(true);
+  });
+
+  it("accepts boolean values in GlobalSettings", () => {
+    const enabled: GlobalSettings = { useLlamaCpp: true };
+    const disabled: GlobalSettings = { useLlamaCpp: false };
+    expect(enabled.useLlamaCpp).toBe(true);
+    expect(disabled.useLlamaCpp).toBe(false);
+  });
+});