Add Starlink status lines for the physical gateway pane (closes #3) (#7)

Detection is a TCP connect to the dish endpoint bound to the physical
interface; once a dish answers, get_status is read every 5s and two
status lines render under the physical pane, red on disconnect or
alert. No dish: nothing drawn, no RPC. Minimal vendored proto bindings
for get_status only. Independent review passed (PR 7 comment 100012).

Model: opus-4-8 (implementation and review); model: claude-fable-5
(merge)

go.mod

@@ -7,6 +7,8 @@ require (
 	github.com/spf13/cobra v1.8.0
 	github.com/spf13/viper v1.18.2
 	golang.org/x/sys v0.29.0
+	google.golang.org/grpc v1.67.1
+	google.golang.org/protobuf v1.36.6
 )
 
 require (
@@ -30,8 +32,10 @@ require (
 	go.uber.org/atomic v1.9.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
+	golang.org/x/net v0.28.0 // indirect
 	golang.org/x/term v0.28.0 // indirect
 	golang.org/x/text v0.21.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240814211410-ddb44dafa142 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )