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/hooks/agent-session-message-state.ts

@@ -19,10 +19,14 @@ import {
 } from "@/features/agent";
 
 type AgentUiDataParts = {
+  agent_message: Record<string, unknown>;
   task_context: Record<string, unknown>;
   execution_plan: Record<string, unknown>;
   progress: Record<string, unknown>;
   final_answer: Record<string, unknown>;
+  credential_refresh_required: Record<string, unknown>;
+  credential_refreshed: Record<string, unknown>;
+  credential_refresh_failed: Record<string, unknown>;
   todo_update: Record<string, unknown>;
   permission_request: Record<string, unknown>;
   permission_response: Record<string, unknown>;
@@ -35,6 +39,7 @@ type AgentUiDataParts = {
   answer_ui: Record<string, unknown>;
   ui_envelope: Record<string, unknown>;
   session_title: Record<string, unknown>;
+  user_input: Record<string, unknown>;
 };
 
 export type AgentUiMessage = UIMessage<unknown, AgentUiDataParts>;
@@ -200,6 +205,15 @@ export function applySessionStreamEvent(messages: AgentUiMessage[], event: Agent
     return toAgentUiMessages(event.messages);
   }
 
+  if (event.type === "user_input") {
+    const id = getDataString(event.data, "id");
+    const text = getDataString(event.data, "text");
+    if (event.data.status !== "delivered" || !id || !text || messages.some((message) => message.id === id)) return messages;
+    const input: AgentUiMessage = { id, role: "user", parts: [{ type: "text", text }] };
+    const tail = messages.at(-1);
+    return tail?.role === "assistant" ? [...messages.slice(0, -1), input, tail] : [...messages, input];
+  }
+
   if (event.type === "token") {
     const token = getDataString(event.data, "content");
     return token ? updateLastAssistantUiMessage(messages, (message) => appendTextToUiMessage(message, token)) : messages;