v2.0.1: ACP dispatch + PTY fallback + worktree management

Phase 5 of v2.0. External agent dispatch via SSH to host.

ACP dispatch (acp-dispatch.ts): spawns agent via SSH with JSON-RPC
stdio pipe. Wraps opencode/goose in ACP mode. Captures structured
events (file operations, tool calls) mapped to parts taxonomy.
Falls back to PTY if ACP handshake fails.

PTY dispatch (pty-dispatch.ts): raw SSH spawn for agents without ACP
support (claude, pi). Captures stdout/stderr as plain text. Simpler
but less structured than ACP.

SSH helper (ssh.ts): shared spawn wrapper for SSH commands to
samkintop@100.114.205.53 (Tailscale IP, same as booterm). Uses
openssh-client installed in the runtime Dockerfile stage.

Worktree management (worktrees.ts): createWorktree (git worktree add
via SSH), diffWorktree (git diff HEAD...task-branch), cleanupWorktree
(git worktree remove --force). One worktree per task at
/tmp/booworktrees/<taskId>.

Dispatcher updated: checks available_agents.supports_acp to pick
transport. Path B flow: create worktree → dispatch agent → diff
worktree → queue diff into pending_changes → cleanup worktree →
mark task complete.

Agent probe updated: probes via SSH to find host-installed agents
(which opencode && opencode --version over SSH).

Dockerfile: openssh-client added to runtime stage.
Config: SSH_HOST env var (default 100.114.205.53).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pnpm-lock.yaml

@@ -48,6 +48,9 @@ importers:
 
   apps/coder:
     dependencies:
+      '@agentclientprotocol/sdk':
+        specifier: ^0.22.1
+        version: 0.22.1(zod@3.25.76)
       '@boocode/server':
         specifier: workspace:*
         version: link:../server
@@ -268,6 +271,11 @@ importers:
 
 packages:
 
+  '@agentclientprotocol/sdk@0.22.1':
+    resolution: {integrity: sha512-DfqXtl/8gO9NImq094MTaCXEU2vkhh6v7q/kT+9UjZxUqj8hYaya2OjLVIqn16MzNHcXEpShTR2RIauLSYeDQQ==}
+    peerDependencies:
+      zod: ^3.25.0 || ^4.0.0
+
   '@ai-sdk/gateway@3.0.119':
     resolution: {integrity: sha512-VAhfRWC+JexZakkVfmjaJKaTj00x7/UHdE8kMWL3NhuQAlf8oXtg9r4dfvFZrByXxchGRBvYE3biEUyibkg0xg==}
     engines: {node: '>=18'}
@@ -4097,6 +4105,10 @@ packages:
 
 snapshots:
 
+  '@agentclientprotocol/sdk@0.22.1(zod@3.25.76)':
+    dependencies:
+      zod: 3.25.76
+
   '@ai-sdk/gateway@3.0.119(zod@3.25.76)':
     dependencies:
       '@ai-sdk/provider': 3.0.10