GODT-1673: TLS certs generation for gRPC service

Wait for Bridge certificate and use it for gRPC connection

Other: add README file for Bridge-GUI prerequisites

GODT-1673: Configure Client/Server to make use of the bridge cert

Other : comments + todo on known issue

Other: fix go import alias [skip-ci]

internal/app/bridge/bridge.go

@@ -162,6 +162,7 @@ func mailLoop(b *base.Base, c *cli.Context) error { //nolint:funlen
 		frontendMode,
 		!c.Bool(base.FlagNoWindow),
 		b.CrashHandler,
+		b.TLS,
 		b.Locations,
 		b.Settings,
 		b.Listener,