Reword comments and docs that still named the removed gRPC stack, rename
the GRPCSortable test interface, and drop the dead gRPC port note from the
dev README.
Add a lightweight dev tool that starts a headscale server on localhost
with a pre-created user and pre-auth key, ready for connecting real
tailscale nodes via mts.
The tool builds the headscale binary, writes a minimal dev config
(SQLite, public DERP, debug logging), starts the server as a
subprocess, and prints a banner with the server URL, auth key, and
mts usage instructions.
Usage: go run ./cmd/dev
make dev-server
Kristoffer Dalby