Merge pull request #1423 from felixriestra:pr/python-host-model

The bundled `opencad.python` plugin drives OCS through plugin API v7: all
43 canvas entity kinds, the drawing tables, and OCS's own commands run
step by step. RustPython stays in the plugin process — the plugin crate is
outside the workspace with its own lock file, so the application's own
dependencies are unchanged.

Reconciled with the plugin command work that landed as #1425, which the
branch was written before:

- Both added `impl Drop for PluginProcessInteractiveAdapter`, which git
  merges silently into two impls that do not compile. One body now
  cancels the command and then drops it from the runner, in that order: a
  plugin waiting on a step has to be released before the runner forgets
  the command.
- `execute_command` (#1425) and `run_command` (#1423) are both routes from
  a script to the command line, and only the second was guarded. The
  SCRIPTCOMMANDS switch and the denylist are shared now, so neither route
  is the unguarded one.
- `run_command` dispatched with plugin dispatch still enabled, so a script
  naming a plugin command re-entered the plugin that was blocked waiting
  for it. It sets the suppression flag for the length of the dispatch, as
  `execute_command` does.

The denylist read the command as typed, while the dispatcher resolves
aliases: a user-defined `Q` for `QUIT` (ALIASEDIT writes those) walked
past it. It resolves the alias first.

Also: the active-command comparison ran on every message, a mouse move
included, allocating two strings for names that are already `&'static
str`; SCRIPTCOMMANDS' own messages go through the translation macros; and
`docs/.DS_Store` (now ignored) and an unrelated RTF note about constraint
commands are out of the tree.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/app/commands/styleprops.rs

@@ -2745,21 +2745,7 @@ impl OpenCADStudio {
                     self.command_line
                         .push_output(crate::tf!("CLAYER = \"{cur}\"").as_ref());
                 } else {
-                    if self.tabs[i].scene.document.layers.contains(name_arg) {
-                        let handle = self.tabs[i]
-                            .scene
-                            .document
-                            .layers
-                            .get(name_arg)
-                            .map(|l| l.handle)
-                            .unwrap_or(acadrust::types::Handle::NULL);
-                        self.tabs[i].scene.document.header.current_layer_name =
-                            name_arg.to_string();
-                        self.tabs[i].scene.document.header.current_layer_handle = handle;
-                        self.tabs[i].active_layer = name_arg.to_string();
-                        self.tabs[i].layers.current_layer = name_arg.to_string();
-                        self.ribbon.active_layer = name_arg.to_string();
-                        self.tabs[i].dirty = true;
+                    if self.set_current_layer_name(i, name_arg).is_ok() {
                         self.command_line
                             .push_output(crate::tf!("CLAYER set to \"{name_arg}\"").as_ref());
                     } else {
@@ -2944,6 +2930,29 @@ impl OpenCADStudio {
                     _ => self.command_line.push_error(crate::t!("Requires 0 or 1").as_ref()),
                 }
             }
+            cmd if cmd == "SCRIPTCOMMANDS" || cmd.starts_with("SCRIPTCOMMANDS ") => {
+                // A user setting, deliberately outside the script's reach: it is refused by
+                // the script command runner, so only the command line can change it.
+                let arg = cmd.trim_start_matches("SCRIPTCOMMANDS").trim();
+                match arg {
+                    "" => {}
+                    "1" | "ON" | "YES" => self.script_commands = true,
+                    "0" | "OFF" | "NO" => self.script_commands = false,
+                    _ => {
+                        self.command_line.push_error(
+                            crate::t!("SCRIPTCOMMANDS takes 1 (scripts may run commands) or 0 (they may not)")
+                                .as_ref(),
+                        );
+                        return Some(Task::none());
+                    }
+                }
+                if !arg.is_empty() {
+                    self.persist_settings_if_changed();
+                }
+                let state = if self.script_commands { 1 } else { 0 };
+                self.command_line
+                    .push_output(crate::tf!("SCRIPTCOMMANDS = {state}").as_ref());
+            }
             "SAVETIME" => {
                 use crate::command::ValuePromptCommand;
                 let c = ValuePromptCommand::new(