Fix tailscale serve: use localhost:PORT, helpful error on Linux

Tailscale serve only supports localhost or 127.0.0.1 as proxy targets.
On Linux, prompts user to run `sudo tailscale set --operator=$USER` if access denied.

Author: jeremy

bin/dev

@@ -35,7 +35,11 @@ if [ "$USE_TAILSCALE" = "1" ]; then
   stop_tailscale() { tailscale serve --https=$TS_PORT off >/dev/null 2>&1; }
   trap stop_tailscale EXIT INT TERM
 
-  sudo tailscale serve --bg --https=$TS_PORT "http://fizzy.localhost:$PORT" >/dev/null 2>&1
+  tailscale serve --bg --https=$TS_PORT localhost:$PORT >/dev/null 2>&1
+  if ! tailscale serve status --json 2>/dev/null | jq -e ".TCP.\"$TS_PORT\"" >/dev/null 2>&1; then
+    echo "Error: tailscale serve failed. On Linux, run once: sudo tailscale set --operator=\$USER" >&2
+    exit 1
+  fi
   echo "Login with david@example.com to: https://$TS_HOSTNAME:$TS_PORT/"
 else
   echo "Login with david@example.com to: http://fizzy.localhost:$PORT/"