feat: implement v2 3-tier architecture (mcpctl → mcplocal → mcpd)

- Rename local-proxy to mcplocal with HTTP server, LLM pipeline, mcpd discovery
- Add LLM pre-processing: token estimation, filter cache, metrics, Gemini CLI + DeepSeek providers
- Add mcpd auth (login/logout) and MCP proxy endpoints
- Update CLI: dual URLs (mcplocalUrl/mcpdUrl), auth commands, --direct flag
- Add tiered health monitoring, shell completions, e2e integration tests
- 57 test files, 597 tests passing

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/mcplocal/tests/discovery.test.ts

@@ -0,0 +1,68 @@
+import { describe, it, expect, vi } from 'vitest';
+import { refreshUpstreams } from '../src/discovery.js';
+import { McpRouter } from '../src/router.js';
+
+function mockMcpdClient(servers: Array<{ id: string; name: string; transport: string }>) {
+  return {
+    baseUrl: 'http://test:3100',
+    token: 'test-token',
+    get: vi.fn(async () => servers),
+    post: vi.fn(async () => ({ result: {} })),
+    put: vi.fn(),
+    delete: vi.fn(),
+    forward: vi.fn(),
+  };
+}
+
+describe('refreshUpstreams', () => {
+  it('registers mcpd servers as upstreams', async () => {
+    const router = new McpRouter();
+    const client = mockMcpdClient([
+      { id: 'srv-1', name: 'slack', transport: 'stdio' },
+      { id: 'srv-2', name: 'github', transport: 'stdio' },
+    ]);
+
+    const registered = await refreshUpstreams(router, client as any);
+    expect(registered).toEqual(['slack', 'github']);
+    expect(router.getUpstreamNames()).toContain('slack');
+    expect(router.getUpstreamNames()).toContain('github');
+  });
+
+  it('removes stale upstreams', async () => {
+    const router = new McpRouter();
+    // First refresh: 2 servers
+    const client1 = mockMcpdClient([
+      { id: 'srv-1', name: 'slack', transport: 'stdio' },
+      { id: 'srv-2', name: 'github', transport: 'stdio' },
+    ]);
+    await refreshUpstreams(router, client1 as any);
+    expect(router.getUpstreamNames()).toHaveLength(2);
+
+    // Second refresh: only 1 server
+    const client2 = mockMcpdClient([
+      { id: 'srv-1', name: 'slack', transport: 'stdio' },
+    ]);
+    await refreshUpstreams(router, client2 as any);
+    expect(router.getUpstreamNames()).toEqual(['slack']);
+  });
+
+  it('does not duplicate existing upstreams', async () => {
+    const router = new McpRouter();
+    const client = mockMcpdClient([
+      { id: 'srv-1', name: 'slack', transport: 'stdio' },
+    ]);
+
+    await refreshUpstreams(router, client as any);
+    await refreshUpstreams(router, client as any);
+    expect(router.getUpstreamNames()).toEqual(['slack']);
+  });
+
+  it('handles empty server list', async () => {
+    const router = new McpRouter();
+    const client = mockMcpdClient([]);
+
+    const registered = await refreshUpstreams(router, client as any);
+    expect(registered).toEqual([]);
+    expect(router.getUpstreamNames()).toHaveLength(0);
+  });
+});