Implement session/fork (agentclientprotocol#183)

Work in progress! Uses a fork for now.

See
agentclientprotocol/agent-client-protocol#277.

---------

Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>

Author: SteffenDE

package-lock.json

@@ -51,7 +51,7 @@
   "author": "Zed Industries",
   "license": "Apache-2.0",
   "dependencies": {
-    "@agentclientprotocol/sdk": "0.9.0",
+    "@agentclientprotocol/sdk": "0.10.0",
     "@anthropic-ai/claude-agent-sdk": "0.1.65",
     "@modelcontextprotocol/sdk": "1.24.3",
     "diff": "8.0.2",