feat: add a tool catalog and local MCP server

Define tools that answer questions from the app's data once, independent
of the surface that exposes them. A tool declares its arguments and the
services it reads; applications compose tools with their own services and
optional call interceptors. Queries reuse the layers' portable source
factories, so they run wherever an application routes /api requests.

The first queries are get_earthquakes, get_active_fires and
get_recent_launches, with a shared area argument (place name, bounding
box, or point and radius) and capped lists.

gods-eye-view/tools/mcp adapts a catalog to the Model Context Protocol
with a small JSON-RPC handler and a stateless HTTP transport, adding no
dependencies. npm run mcp serves Core's tools over stdio to local clients
such as Claude Code, reading from a running app. Both exports are
portable and checked by check:boundaries; the app does not import them.

server/mcp/services.js

@@ -0,0 +1,39 @@
+/**
+ * Local composition of tool services: the portable source factories, pointed
+ * at a running God's Eye View server's `/api` routes.
+ */
+
+import { createUsgsEarthquakeSource } from '../../src/layers/earthquakes/source.js';
+import { createFirmsSource } from '../../src/layers/firms/source.js';
+import { createLaunchSource } from '../../src/layers/launches/source.js';
+import { createGeocodePlaceService } from '../../src/tools/places.js';
+
+export const DEFAULT_API_BASE = 'http://localhost:4173';
+
+/** Resolve the sources' relative `/api/...` requests against `apiBase`. */
+export function createApiFetch({
+  apiBase = DEFAULT_API_BASE,
+  fetchImpl = (...args) => globalThis.fetch(...args),
+} = {}) {
+  const base = new URL(apiBase);
+  if (!['http:', 'https:'].includes(base.protocol))
+    throw new TypeError(`apiBase must be an http(s) URL: ${apiBase}`);
+  return (input, init) =>
+    fetchImpl(
+      typeof input === 'string' && input.startsWith('/')
+        ? new URL(input, base)
+        : input,
+      init,
+    );
+}
+
+/** Construct every service Core's tools read, backed by the local server. */
+export function createLocalToolServices(options = {}) {
+  const fetchImpl = createApiFetch(options);
+  return {
+    earthquakes: createUsgsEarthquakeSource({ fetchImpl }),
+    fires: createFirmsSource({ fetchImpl }),
+    launches: createLaunchSource({ fetchImpl }),
+    places: createGeocodePlaceService({ fetchImpl }),
+  };
+}