Merge PR #1585 from ramox81/codex/field-command: FIELD command and Field dialog; attribute definition field buttons

The PR pinned the codec to its fork through [patch]; codec #75 is merged
upstream and main already points at it, so the patch section is dropped.
The two windows-sys features it adds (Globalization, Identity) stay.

src/app/mod.rs

@@ -501,6 +501,8 @@ pub(super) struct OpenCADStudio {
     /// ATTDEF dialog and Edit Attribute Definition dialog; `None` while closed.
     attdef_dialog: Option<crate::ui::window::attdef_dialog::AttdefDialogState>,
     attdef_edit: Option<crate::ui::window::attdef_dialog::AttdefEditState>,
+    /// Field dialog working copy; `None` while closed.
+    field_dialog: Option<crate::ui::window::field_dialog::FieldDialogState>,
     point_cloud_color_map: Option<crate::ui::window::pdf_dialogs::PointCloudColorMapState>,
     pc_section: Option<crate::ui::window::pdf_dialogs::PcSectionState>,
     underlay_layers: Option<crate::ui::window::pdf_dialogs::UnderlayLayersState>,
@@ -1938,6 +1940,7 @@ pub enum ModalKind {
     GeometricTolerance,
     AttDef,
     AttDefEdit,
+    Field,
     DraftingSettings,
     AutoConstrainSettings,
     LayerStateEditor,
@@ -3891,6 +3894,7 @@ pub enum Message {
     /// An edit in one of the PDF dialogs.
     PdfDialog(crate::ui::window::pdf_dialogs::PdfDialogMsg),
     AttdefDialog(crate::ui::window::attdef_dialog::AttdefDialogMsg),
+    FieldDialog(crate::ui::window::field_dialog::FieldDialogMsg),
     /// A click or search in the Point Cloud Manager.
     PcManager(crate::ui::window::pc_manager::PcManagerMsg),
     PdfImportPickResult(Result<(std::path::PathBuf, std::sync::Arc<Vec<u8>>), String>),
@@ -4086,6 +4090,7 @@ impl OpenCADStudio {
             point_cloud_attach: None,
             attdef_dialog: None,
             attdef_edit: None,
+            field_dialog: None,
             point_cloud_color_map: None,
             pc_section: None,
             underlay_layers: None,