fix(junie): remove JUNIE_MODEL env var to fix 'Unknown model: openrouter/auto' crash (#2735)

Junie only accepts its own shorthand model names (gpt, opus, sonnet, etc.)
and not OpenRouter model IDs. Removing modelEnvVar lets junie handle its
own model routing via the OpenRouter API key instead.

Fixes #2734

Agent: code-health

Co-authored-by: B <6723574+louisgv@users.noreply.github.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@openrouter/spawn",
-  "version": "0.21.1",
+  "version": "0.21.2",
   "type": "module",
   "bin": {
     "spawn": "cli.js"

packages/cli/src/shared/agent-setup.ts

@@ -1037,7 +1037,6 @@ function createAgents(runner: CloudRunner): Record<string, AgentConfig> {
     junie: {
       name: "Junie",
       cloudInitTier: "node",
-      modelEnvVar: "JUNIE_MODEL",
       preProvision: detectGithubAuth,
       install: () =>
         installAgent(