feat(agent): support Responses steering and project-aware tools

Use the dedicated TJWATER_AGENT_URL and Responses stream protocol. Keep running
turns active while users steer or queue follow-ups and edit pending delivery.
Refresh the model catalog before generation and preserve approval mode selection.

Integrate scoped investigation messaging/presentation, geographic place selection,
current Agent composer styles and supporting workbench contracts.

Validation: 77 focused Vitest checks, 21 browser cases, lint, typecheck and
production build. Preserve direct Server/Agent routing and project authentication.

src/features/workbench/map/geocoding-location.ts

@@ -0,0 +1,22 @@
+import { Marker, type Map as MapLibreMap, type PaddingOptions } from "maplibre-gl";
+import type { PlaceSearchItem } from "../api/place-search-client";
+
+export function markGeocodingLocation(map: MapLibreMap, result: PlaceSearchItem) {
+  const marker = new Marker({ color: "var(--action-blue)" })
+    .setLngLat([result.longitude, result.latitude]).addTo(map);
+  const element = marker.getElement();
+  element.dataset.geocodingMarker = "true";
+  element.setAttribute("role", "img");
+  element.setAttribute("aria-label", `地址定位：${result.name} ${result.address}`);
+  element.title = `${result.name} · ${result.address}`;
+  return marker;
+}
+
+export function locateGeocodingResult(map: MapLibreMap, result: PlaceSearchItem, padding: PaddingOptions, reducedMotion: boolean) {
+  map.easeTo({
+    center: [result.longitude, result.latitude],
+    zoom: 16,
+    padding,
+    duration: reducedMotion ? 0 : 500
+  });
+}