fix(ui): refine command line and clipboard

- preserve command history colors after reopening
- remove collapsed command bar residue and split the unsaved prompt
- read system text when the drawing clipboard is empty

Refs #467
Refs #468
Refs #470

src/app/commands/blocks.rs

@@ -193,7 +193,7 @@ impl OpenCADStudio {
 
             "PASTECLIP" => {
                 if self.clipboard.is_empty() {
-                    self.command_line.push_error(crate::t!("Clipboard is empty.").as_ref());
+                    return Some(self.read_system_clipboard_for_paste());
                 } else {
                     let wires = self.tabs[i].scene.wires_for_entities(&self.clipboard);
                     let base = self.clipboard_base;

src/app/mod.rs

@@ -1586,10 +1586,11 @@ pub enum Message {
         crate::scene::text::web_font::Script,
         Result<(), String>,
     ),
-    /// Ctrl+V. Routed by `update`: into the open text/MText editor (via an async
-    /// system-clipboard read, which is the only paste path that works on the
-    /// web) or, with no editor open, the entity paste command.
+    /// Ctrl+V. Routed by `update` into an open text editor, the drawing-object
+    /// clipboard, or the system text clipboard.
     PasteShortcut,
+    /// Completion of a system text clipboard read requested by PASTECLIP.
+    SystemClipboardPaste(SystemClipboardText),
     /// Ctrl/Cmd+A — select all layer rows when the Layer Manager is open, or all
     /// drawing objects otherwise (#236).
     SelectAllShortcut,
@@ -2791,6 +2792,15 @@ pub enum Message {
     ),
 }
 
+#[derive(Debug, Clone)]
+pub enum SystemClipboardText {
+    Text(String),
+    EmptyOrUnsupported,
+    Unavailable,
+    Occupied,
+    ConversionFailed,
+}
+
 impl OpenCADStudio {
     /// Install the Start-page video list, decoding each thumbnail's JPEG into
     /// an image Handle exactly once (a fresh Handle per view frame would

src/app/update/command.rs

@@ -1259,7 +1259,44 @@ pub(super) fn on_tab_close(&mut self, idx: usize) -> Task<Message> {
                     #[cfg(not(target_arch = "wasm32"))]
                     return Task::none();
                 }
-                Task::done(Message::Command("PASTECLIP".to_string()))
+                if self.clipboard.is_empty() {
+                    self.read_system_clipboard_for_paste()
+                } else {
+                    Task::done(Message::Command("PASTECLIP".to_string()))
+                }
+    }
+
+    pub(in crate::app) fn read_system_clipboard_for_paste(&self) -> Task<Message> {
+        #[cfg(target_arch = "wasm32")]
+        {
+            Task::perform(crate::sys::read_clipboard_text(), |text| {
+                Message::SystemClipboardPaste(match text {
+                    Some(text) if !text.is_empty() => {
+                        crate::app::SystemClipboardText::Text(text)
+                    }
+                    _ => crate::app::SystemClipboardText::EmptyOrUnsupported,
+                })
+            })
+        }
+
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            iced::clipboard::read_text().map(|result| {
+                use crate::app::SystemClipboardText as Text;
+                use iced::clipboard::Error;
+
+                let result = match result {
+                    Ok(text) if !text.is_empty() => Text::Text((*text).clone()),
+                    Ok(_) | Err(Error::ContentNotAvailable) => Text::EmptyOrUnsupported,
+                    Err(Error::ClipboardUnavailable) | Err(Error::Unknown { .. }) => {
+                        Text::Unavailable
+                    }
+                    Err(Error::ClipboardOccupied) => Text::Occupied,
+                    Err(Error::ConversionFailure) => Text::ConversionFailed,
+                };
+                Message::SystemClipboardPaste(result)
+            })
+        }
     }
 
     pub(super) fn on_qselect_open(&mut self) -> Task<Message> {

src/app/update/mod.rs

@@ -3585,10 +3585,44 @@ impl OpenCADStudio {
             // Ctrl+V. The MText editor and (on the web) the TEXT editor read the
             // system clipboard asynchronously — the only paste path that works
             // in the browser, where the synchronous clipboard the iced
-            // text_input expects is empty. With no editor open it falls through
-            // to the entity paste command.
+            // text_input expects is empty. With no editor open, drawing objects
+            // take priority and system text is used when that clipboard is empty.
             Message::PasteShortcut => self.on_paste_shortcut(),
 
+            Message::SystemClipboardPaste(result) => {
+                use super::SystemClipboardText as Text;
+
+                match result {
+                    Text::Text(text) => {
+                        let flat = text.replace(['\r', '\n'], " ").to_uppercase();
+                        self.command_line.input.push_str(&flat);
+                        self.command_line.autocomplete_cursor = None;
+                        self.focus_cmd_input()
+                    }
+                    Text::EmptyOrUnsupported => {
+                        self.command_line.push_error(
+                            crate::tr!("clipboard-no-supported-content").as_ref(),
+                        );
+                        Task::none()
+                    }
+                    Text::Unavailable => {
+                        self.command_line
+                            .push_error(crate::tr!("clipboard-unavailable").as_ref());
+                        Task::none()
+                    }
+                    Text::Occupied => {
+                        self.command_line
+                            .push_error(crate::tr!("clipboard-occupied").as_ref());
+                        Task::none()
+                    }
+                    Text::ConversionFailed => {
+                        self.command_line
+                            .push_error(crate::tr!("clipboard-conversion-failed").as_ref());
+                        Task::none()
+                    }
+                }
+            }
+
             Message::SelectAllShortcut => {
                 let i = self.active_tab;
                 if self.mtext_editor.as_ref().is_some_and(|e| e.show_preview) {

src/app/view/modal.rs

@@ -1475,14 +1475,13 @@ fn unsaved_changes_dialog_window(
     name: &str,
     sizing: crate::ui::modal::ModalSizing,
 ) -> Element<'static, Message> {
-    let body_text = t!(
-        "Do you want to save changes to \"%{name}\"?",
-        name = name
-    );
-
     container(
         column![
-            text(body_text).size(13),
+            text(name.to_owned()).size(14),
+            iced::widget::Space::new().height(4),
+            text(crate::tr!("modal-unsaved-save-prompt"))
+                .size(12)
+                .style(dialog_muted_text_style),
             iced::widget::Space::new().height(20),
             row![
                 dialog_button(t!("Save"), Message::UnsavedDialogSave, button::primary),