feat: add Nostr channel plugin and onboarding install defaults

Co-authored-by: joelklabo <joelklabo@users.noreply.github.com>

src/commands/onboarding/plugin-install.test.ts

@@ -102,6 +102,52 @@ describe("ensureOnboardingPluginInstalled", () => {
     expect(result.cfg.plugins?.entries?.zalo?.enabled).toBe(true);
   });
 
+  it("defaults to local on dev channel when local path exists", async () => {
+    const runtime = makeRuntime();
+    const select = vi.fn(async () => "skip") as WizardPrompter["select"];
+    const prompter = makePrompter({ select });
+    const cfg: ClawdbotConfig = { update: { channel: "dev" } };
+    vi.mocked(fs.existsSync).mockImplementation((value) => {
+      const raw = String(value);
+      return (
+        raw.endsWith(`${path.sep}.git`) || raw.endsWith(`${path.sep}extensions${path.sep}zalo`)
+      );
+    });
+
+    await ensureOnboardingPluginInstalled({
+      cfg,
+      entry: baseEntry,
+      prompter,
+      runtime,
+    });
+
+    const firstCall = select.mock.calls[0]?.[0];
+    expect(firstCall?.initialValue).toBe("local");
+  });
+
+  it("defaults to npm on beta channel even when local path exists", async () => {
+    const runtime = makeRuntime();
+    const select = vi.fn(async () => "skip") as WizardPrompter["select"];
+    const prompter = makePrompter({ select });
+    const cfg: ClawdbotConfig = { update: { channel: "beta" } };
+    vi.mocked(fs.existsSync).mockImplementation((value) => {
+      const raw = String(value);
+      return (
+        raw.endsWith(`${path.sep}.git`) || raw.endsWith(`${path.sep}extensions${path.sep}zalo`)
+      );
+    });
+
+    await ensureOnboardingPluginInstalled({
+      cfg,
+      entry: baseEntry,
+      prompter,
+      runtime,
+    });
+
+    const firstCall = select.mock.calls[0]?.[0];
+    expect(firstCall?.initialValue).toBe("npm");
+  });
+
   it("falls back to local path after npm install failure", async () => {
     const runtime = makeRuntime();
     const note = vi.fn(async () => {});