improv: error handling

- Errors are now defined via thiserror
- CLI app updated to use crate::error::Error instead of anyhow

Author: edfloreshz

.gitignore

@@ -8,11 +8,10 @@
 # These are backup files generated by rustfmt
 **/*.rs.bk
 */target
-Cargo.lock
 *.out
 /.out/
 /.idea
 *.DS_Store
 .vscode
 .tasks
-.vimspector.json
+.vimspector.json