fix: unset CLAUDECODE in spawned sessions to prevent nested session errors

The spawn command was creating tmux sessions without calling agent.getEnvironment(),
causing spawned sessions to inherit CLAUDECODE from the parent orchestrator session.
This caused Claude to refuse to start with "cannot launch inside another Claude Code
session" error.

Now properly calls agent.getEnvironment() and merges those env vars (including
CLAUDECODE="") into the tmux session creation.

Fixes sessions ao-22 through ao-25 which were spawned but never had Claude running.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

packages/cli/src/commands/spawn.ts

@@ -133,9 +133,17 @@ async function spawnSession(
 
     spinner.text = "Creating tmux session";
 
+    // Get agent-specific environment variables (e.g., unset CLAUDECODE)
+    const agentEnv = agent.getEnvironment({
+      sessionId: sessionName,
+      projectConfig: project,
+      issueId,
+      permissions: project.agentConfig?.permissions,
+    });
+
     // Create tmux session
     const envVar = `${prefix.toUpperCase().replace(/[^A-Z0-9_]/g, "_")}_SESSION`;
-    await exec("tmux", [
+    const tmuxArgs = [
       "new-session",
       "-d",
       "-s",
@@ -152,7 +160,14 @@ async function spawnSession(
       `AO_DATA_DIR=${config.dataDir}`,
       "-e",
       "DIRENV_LOG_FORMAT=",
-    ]);
+    ];
+
+    // Add agent environment variables
+    for (const [key, value] of Object.entries(agentEnv)) {
+      tmuxArgs.push("-e", `${key}=${value}`);
+    }
+
+    await exec("tmux", tmuxArgs);
 
     // Run post-create hooks before agent launch (so environment is ready)
     if (project.postCreate) {