Introducing auto approvers for routes and exit nodes

Tailscale introduces the concept of autoApprovers for routes and exit nodes, allowing users to self-approve network configurations specified in an Access Control List (ACL) file. This feature simplifies the setup process for subnet routers and exit nodes by enabling users to manage multiple devices with a single command without needing post-setup admin approval. Subnet routers facilitate the connection of existing private networks to a Tailscale tailnet, offering an efficient method to deploy Tailscale incrementally without installing it on every device. However, while subnet routers ease deployment, they rely on trusted networks since they do not provide end-to-end encryption like direct Tailscale installations, which are recommended for zero-trust networks for enhanced security and performance. AutoApprovers streamline the management of network routes and exit nodes by allowing designated users to handle route advertisement and approval, which is particularly useful for high-availability deployments and dynamic network management.