feat: collect structured turns from ACP session updates

UwfAcpClient now tracks all session/update events:
- agent_message_chunk → assistant message content
- agent_thought_chunk → assistant reasoning
- tool_call → pending tool invocation (name + rawInput)
- tool_call_update (completed/failed) → assistant tool_call + tool result

Messages are accumulated across prompts (same session) and stored
via storeHermesSessionDetail, restoring the full structured detail
(turns with tool calls, reasoning) that was lost in the initial ACP
migration.

Ref #398

packages/workflow-agent-hermes/__tests__/acp-client.test.ts

@@ -53,4 +53,25 @@ describe("HermesAcpClient", () => {
     },
     { timeout: 2 * 60 * 1000 },
   );
+
+  it(
+    "prompt() collects structured messages including tool calls",
+    async () => {
+      await client.connect(process.cwd());
+      const result = await client.prompt("Run this command: echo TOOL_DETAIL_TEST");
+      expect(result.messages.length).toBeGreaterThan(0);
+      // Should have at least one tool message (the echo command)
+      const toolMessages = result.messages.filter((m) => m.role === "tool");
+      expect(toolMessages.length).toBeGreaterThan(0);
+      // Tool message should contain the output
+      const toolContent = toolMessages[0]?.content ?? "";
+      expect(toolContent).toContain("TOOL_DETAIL_TEST");
+      // Should have assistant messages with tool_calls
+      const assistantWithTools = result.messages.filter(
+        (m) => m.role === "assistant" && m.tool_calls !== null,
+      );
+      expect(assistantWithTools.length).toBeGreaterThan(0);
+    },
+    { timeout: 2 * 60 * 1000 },
+  );
 });