feat(FN-2477): add executable OpenClaw runtime adapter

- Replace deferred OpenClaw placeholder runtime with an executable adapter that creates sessions, prompts with fallback, describes models, and disposes safely
- Add a dedicated pi-module seam and local runtime contract types to decouple plugin compilation from engine internals while preserving runtime behavior
- Update OpenClaw plugin metadata, manifest/package descriptions, and README to reflect active execution support instead of deferred status
- Harden dashboard DevServerStore save flow against ENOENT temp-directory races and add regression coverage for project-directory removal during save

plugins/fusion-plugin-openclaw-runtime/src/__tests__/runtime-adapter.test.ts

@@ -0,0 +1,97 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { OpenClawRuntimeAdapter } from "../runtime-adapter.js";
+
+const { mockCreateFnAgent, mockPromptWithFallback, mockDescribeModel } = vi.hoisted(() => ({
+  mockCreateFnAgent: vi.fn(),
+  mockPromptWithFallback: vi.fn(),
+  mockDescribeModel: vi.fn(),
+}));
+
+vi.mock("../pi-module.js", () => ({
+  createFnAgent: mockCreateFnAgent,
+  promptWithFallback: mockPromptWithFallback,
+  describeModel: mockDescribeModel,
+}));
+
+describe("OpenClawRuntimeAdapter", () => {
+  let adapter: OpenClawRuntimeAdapter;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockDescribeModel.mockReturnValue("mock/anthropic-claude");
+    adapter = new OpenClawRuntimeAdapter();
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it("has stable runtime identity", () => {
+    expect(adapter.id).toBe("openclaw");
+    expect(adapter.name).toBe("OpenClaw Runtime");
+  });
+
+  it("delegates createSession to createFnAgent with mapped options", async () => {
+    const mockSession = { dispose: vi.fn() };
+    mockCreateFnAgent.mockResolvedValue({ session: mockSession, sessionFile: "/tmp/session.json" });
+
+    const result = await adapter.createSession({
+      cwd: "/project",
+      systemPrompt: "You are helpful",
+      defaultProvider: "anthropic",
+      defaultModelId: "claude-sonnet-4-5",
+      fallbackProvider: "openai",
+      fallbackModelId: "gpt-4o",
+      skills: ["bash"],
+    });
+
+    expect(mockCreateFnAgent).toHaveBeenCalledWith({
+      cwd: "/project",
+      systemPrompt: "You are helpful",
+      tools: undefined,
+      customTools: undefined,
+      onText: undefined,
+      onThinking: undefined,
+      onToolStart: undefined,
+      onToolEnd: undefined,
+      defaultProvider: "anthropic",
+      defaultModelId: "claude-sonnet-4-5",
+      fallbackProvider: "openai",
+      fallbackModelId: "gpt-4o",
+      defaultThinkingLevel: undefined,
+      sessionManager: undefined,
+      skillSelection: undefined,
+      skills: ["bash"],
+    });
+    expect(result.session).toBe(mockSession);
+    expect(result.sessionFile).toBe("/tmp/session.json");
+  });
+
+  it("delegates promptWithFallback to pi seam", async () => {
+    const session = { id: "s-1" };
+    mockPromptWithFallback.mockResolvedValue(undefined);
+
+    await adapter.promptWithFallback(session as any, "Hello", { images: [] });
+
+    expect(mockPromptWithFallback).toHaveBeenCalledWith(session, "Hello", { images: [] });
+  });
+
+  it("delegates describeModel to pi seam", () => {
+    const session = { id: "s-2" };
+    mockDescribeModel.mockReturnValue("anthropic/claude-sonnet-4-5");
+
+    const result = adapter.describeModel(session as any);
+
+    expect(mockDescribeModel).toHaveBeenCalledWith(session);
+    expect(result).toBe("anthropic/claude-sonnet-4-5");
+  });
+
+  it("dispose calls session.dispose when present and no-ops otherwise", async () => {
+    const disposeMock = vi.fn().mockResolvedValue(undefined);
+
+    await adapter.dispose({ dispose: disposeMock });
+    await expect(adapter.dispose({ id: "no-dispose" } as any)).resolves.toBeUndefined();
+
+    expect(disposeMock).toHaveBeenCalledTimes(1);
+  });
+});