- set version from `runtime/debug.Main.Version`
- use latest git tag as fallback
- allow version to be overwritten via ldflags
- this will break `go build .` and `go install .`
- add `Connected()` method for client
- add `LastErr` field to GoTomatoClient
- replace error logging by updating `LastErr` field
- modify methods to use pointer receivers for Client
- add `prevMessage` variable to store the last received server message
- show connect status in TUI
- use EnterAltScreen instead of ClearScreen
