feat: log local MCP requests to stderr by method

The stdio server writes each request's method, and the tool or resource it
names, to stderr, which clients such as Claude Desktop copy into their logs.
Arguments and results are never logged.

src/tools/localServer.test.mjs

@@ -87,3 +87,20 @@ test('command-line arguments are strict', () => {
   });
   assert.throws(() => parseArgs(['--port', '1']), /Unknown argument/);
 });
+
+test('the stdio log names methods, tools and resources but never arguments', async () => {
+  const { describeRequest } = await import('../../server/mcp/stdio.js');
+  assert.equal(describeRequest({ method: 'tools/list' }), 'tools/list');
+  assert.equal(
+    describeRequest({
+      method: 'tools/call',
+      params: { name: 'get_weather', arguments: { location: { place: 'x' } } },
+    }),
+    'tools/call get_weather',
+  );
+  assert.equal(
+    describeRequest({ method: 'resources/read', params: { uri: 'ui://a/b' } }),
+    'resources/read ui://a/b',
+  );
+  assert.equal(describeRequest({ result: {} }), null);
+});