fix(commands): record last_cmd on plugin dispatch to repeat on Enter

When a plugin command was dispatched, record_recent was called but
tabs[i].last_cmd was never set. Consequently, pressing Enter or Space on
an empty command line after running a plugin command failed to repeat it.

This records tabs[i].last_cmd on plugin dispatch and requests command-line
focus and dynamic input syncing when an interactive plugin command starts.

src/app/command_driver/utilities.rs

@@ -731,6 +731,8 @@ impl OpenCADStudio {
         // (`LINE`), so the full line is not a plugin command and falls through to
         // the first-word + fed-tokens path below. (#162)
         if !self.suppress_plugin_dispatch && crate::plugin::try_dispatch(self, i, cmd) {
+            self.tabs[i].last_cmd = Some(cmd.to_string());
+            self.command_line.record_recent(cmd);
             let toks: Vec<String> = tokens.iter().map(|s| s.to_string()).collect();
             return self.finish_active_command(&toks, finish);
         }