fix(favourite-index): route favourite/ calls even before tools/list (lazy resolver)

The presented→canonical resolver was only built during tools/list, so a
favourite/<tool> call arriving before any list this session fell through to the
namespaced router and 404'd (all/ was fine — it prefix-strips). Real MCP clients
list first, but the smoke test's initialize→call flow exposed it. Extract
buildPresentation() and lazily rebuild the resolver in onToolCallBefore when a
favourite//all/ name isn't resolved yet. + unit test (favourite/ call with no
prior list) and realistic listTools() in the smoke routing case.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/mcplocal/tests/plugin-favourite-index.test.ts

@@ -134,6 +134,19 @@ describe('favourite-index plugin', () => {
     expect(text).toBe('Called scale_deployment');
   });
 
+  it('routes a favourite/ call even before tools/list (lazy resolver rebuild)', async () => {
+    const router = setup({ favourites: ['vault/read_secret'] });
+    router.addUpstream(mockUpstream('vault', CATALOG.vault));
+    // initialize only — deliberately NO tools/list, so the resolver is unset.
+    await router.route({ jsonrpc: '2.0', id: 1, method: 'initialize' }, { sessionId: 's1' });
+
+    const res = await router.route(
+      { jsonrpc: '2.0', id: 2, method: 'tools/call', params: { name: 'favourite/read_secret', arguments: {} } },
+      { sessionId: 's1' },
+    );
+    expect((res.result as { content: Array<{ text: string }> }).content[0]!.text).toBe('Called read_secret');
+  });
+
   it('no-ops while the session is gated (only begin_session visible)', async () => {
     const router = setup({ gated: true, favourites: ['k8s/get_pods'] });
     router.addUpstream(mockUpstream('k8s', CATALOG.k8s));

src/mcplocal/tests/smoke/favourite-index.test.ts

@@ -104,6 +104,7 @@ describe('Smoke: favourite-index presentation', () => {
     chat.section('favourite-index routing');
     try {
       await chat.initialize();
+      await chat.listTools(); // real clients list before calling — populates the resolver
 
       // Calling with no args → the UPSTREAM tool's arg validation fires, proving
       // the presented name routed to the real server (not a -32601 unknown tool).