feat(server): integrate MCP queries and investigation messaging

Add project-bound OAuth MCP queries and controlled analysis with scoped evidence,
limits, timeouts and a nearby-model spatial query using EPSG:4326 inputs.
Default nearby searches to 200 meters and five results.

Integrate investigation messaging/presentation, health/readiness and typed history;
remove duplicate web search and fix online simulation and compressed baseline writes.
Include project migrations 023-025; keep local credentials and demo seeding excluded.

Validation: 319 focused pytest checks; real PostGIS temporary-table regression;
read-only Jinqian bridge radius comparison; cross-language MCP discovery/calls.

app/mcp/dispatch.py

@@ -0,0 +1,15 @@
+"""Delegate MCP transport/metadata with the original request path intact."""
+
+
+class McpDispatchMiddleware:
+    def __init__(self, app, runtime):
+        self.app, self.runtime = app, runtime
+
+    async def __call__(self, scope, receive, send):
+        path = scope.get("path", "")
+        if scope["type"] == "http" and (
+            path == "/mcp" or path.startswith("/.well-known/oauth-protected-resource")
+        ):
+            await self.runtime.asgi(scope, receive, send)
+        else:
+            await self.app(scope, receive, send)