fix: tolerate ssh failures, drop vendored binary

- query each server independently for app status so ssh login issues no
  longer abort the whole poll (partial results still render)
- show ssh/server errors as a dismissible banner instead of a dead-end
  error screen; any key dismisses and s can be retried
- guard against concurrent status polls
- stop tracking the compiled cctuip binary, add .gitignore
- add -v/--version flag, remove dead code, harden type assertions,
  cache recipe catalogue lookups
- align README install + controls with the code

.gitignore

@@ -0,0 +1,2 @@
+cctuip
+*.exe