feat: exec mode improvements

Use Bollard library to exec in pure Rust.

`--use-cli` cli arg, will then only try to exec into containers using
Docker.

Only try to exec into a container if the state == Running.

src/app_error.rs

@@ -27,7 +27,7 @@ impl fmt::Display for AppError {
                 let reason = if *x { "en" } else { "dis" };
                 write!(f, "Unable to {reason}able mouse capture")
             }
-            Self::Terminal => write!(f, "Unable to draw to terminal"),
+            Self::Terminal => write!(f, "Unable to fully render to terminal"),
         }
     }
 }