feat(agent-zero): Zulip adapter with A2A protocol for kagentz

New project: agent-zero-zulip/ — direct Zulip integration for Agent Zero
agents using A2A protocol internally.

Architecture:
  kagentz (CT 105) ┌──────────────────────┐
                    │ Zulip Adapter  ◄──►  │ Agent Zero
                    │ polls Zulip    A2A   │ Docker container
                    │ port 8001            │
                    └──────────────────────┘

- adapter.py: Zulip event queue poller + A2A client
- No intermediate bridge — direct kagentz ↔ Zulip
- Heartbeat, reconnection, placeholder→edit streaming
- Designed for re-use: scottdenya, future Agent Zero agents

agent-zero-zulip/DEPLOY.md

@@ -0,0 +1,48 @@
+# Deploy Agent Zero Zulip Adapter
+
+## Prerequisites
+- Agent Zero running in Docker on the target CT
+- A Zulip bot created for the agent (kagentz-bot, scottdenya-bot, etc.)
+- Python 3.11+ with httpx
+
+## Steps
+
+### 1. Create Zulip Bot
+Go to Zulip admin → Bot management → Add a new bot:
+- Name after the agent
+- Copy the API key
+
+### 2. Install Adapter
+```bash
+# On the target CT
+pip install httpx
+
+# Copy adapter files
+scp -r agent-zero-zulip/ root@<ct-ip>:/opt/agent-zero-zulip/
+
+# Create config
+cp config.yaml.example config.yaml
+# Edit config.yaml with Zulip credentials
+```
+
+### 3. Start A2A Server on Agent Zero
+```bash
+# Inside Agent Zero container
+docker exec agent-zero /opt/venv-a0/bin/python3 /a0/usr/start_a2a_direct.py &
+
+# Verify A2A is running
+curl http://localhost:8001/.well-known/agent.json
+```
+
+### 4. Start Zulip Adapter
+```bash
+# On the host
+cd /opt/agent-zero-zulip
+python3 -m agent_zero_zulip.adapter &
+
+# Verify
+tail -f adapter.log
+```
+
+### 5. Test
+Send a DM to kagentz-bot in Zulip. Expect "Processing..." → response.