feat(dimstyle): add Annotative toggle to the Dimension Style editor

Adds the annotative property (DsField::Annotative) to the dim-style edit
buffers, load/apply, and a checkbox on the Fit/Scale tab — consistent with
the Text Style editor's annotative toggle.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/app/mod.rs

@@ -390,6 +390,7 @@ pub(super) struct OpenCADStudio {
     ds_dimtm: String,
     ds_dimtdec: String,
     ds_dimtfac: String,
+    ds_annotative: bool,
 }
 
 /// What triggered the "unsaved changes" dialog.
@@ -432,6 +433,7 @@ pub enum DsField {
     Dimtm,
     Dimtdec,
     Dimtfac,
+    Annotative,
 }
 
 #[derive(Debug, Clone)]
@@ -1100,6 +1102,7 @@ impl OpenCADStudio {
             ds_dimtm: "0".to_string(),
             ds_dimtdec: "2".to_string(),
             ds_dimtfac: "1".to_string(),
+            ds_annotative: false,
         };
         app.sync_ribbon_layers();
         app

src/app/update.rs

@@ -6500,6 +6500,7 @@ impl OpenCADStudio {
         self.ds_dimtm = format!("{}", ds.dimtm);
         self.ds_dimtdec = format!("{}", ds.dimtdec);
         self.ds_dimtfac = format!("{}", ds.dimtfac);
+        self.ds_annotative = ds.annotative;
     }
 
     /// Write edit buffers back into the selected dim style document entry.
@@ -6551,6 +6552,7 @@ impl OpenCADStudio {
         ds.dimlim = self.ds_dimlim;
         ds.dimpost = self.ds_dimpost.clone();
         ds.dimtxsty = self.ds_dimtxsty.clone();
+        ds.annotative = self.ds_annotative;
         self.tabs[tab].dirty = true;
         self.command_line
             .push_output(&format!("DimStyle '{}' updated.", self.dimstyle_selected));
@@ -6597,6 +6599,7 @@ impl OpenCADStudio {
             Dimtoh => self.ds_dimtoh = !self.ds_dimtoh,
             Dimtol => self.ds_dimtol = !self.ds_dimtol,
             Dimlim => self.ds_dimlim = !self.ds_dimlim,
+            Annotative => self.ds_annotative = !self.ds_annotative,
             _ => {}
         }
     }

src/app/view.rs

@@ -215,6 +215,7 @@ impl OpenCADStudio {
                     dimtm: &self.ds_dimtm,
                     dimtdec: &self.ds_dimtdec,
                     dimtfac: &self.ds_dimtfac,
+                    annotative: self.ds_annotative,
                 },
             );
         }

src/ui/dimstyle.rs

@@ -89,6 +89,7 @@ pub struct DimStyleValues<'a> {
     pub dimtm: &'a str,
     pub dimtdec: &'a str,
     pub dimtfac: &'a str,
+    pub annotative: bool,
 }
 
 fn btn_s(accent: bool) -> impl Fn(&Theme, button::Status) -> button::Style {
@@ -422,6 +423,7 @@ pub fn view_window<'a>(
         .into(),
         3 => column![
             text("Scale").size(11).color(ACCENT),
+            chk("Annotative", vals.annotative, DsField::Annotative),
             row![
                 lbl("Overall scale (DIMSCALE)"),
                 mk_field(DsField::Dimscale, vals.dimscale)