feat(FN-2981): add droid-cli auth and status routes with experimental agent

This merge lands v0.12.0 with two major features: a droid-cli provider integration adding auth routes, status endpoints, and a settings toggle hook for controlling CLI-based authentication, plus a new experimental agent onboarding modal with a create-agent form. The release also stabilizes engine st

Fusion-Task-Id: FN-2981

packages/cli/src/commands/provider-auth.ts

@@ -49,7 +49,7 @@ const BUILT_IN_API_KEY_PROVIDERS: Array<{ id: string; name: string }> = [
   { id: "zai", name: "Zai" },
 ];
 
-const CLI_PROVIDER_IDS = new Set(["pi-claude-cli"]);
+const CLI_PROVIDER_IDS = new Set(["pi-claude-cli", "droid-cli"]);
 
 function getProviderDisplayName(providerId: string): string {
   const knownProviderNames = new Map(