feat(ui): persistent literal-space toggle on the command line

'>' button after the Command: label turns the leading-'>' literal-space
behavior into a mode: while on, Space stays in the line instead of
submitting, until toggled off. State persists in settings.json; a
hand-typed leading '>' still works for a single line.

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

src/app/mod.rs

@@ -1364,6 +1364,10 @@ pub enum Message {
     CommandHistoryNext,
     /// Toggle the dropdown listing the full command-line history.
     CommandHistoryToggle,
+    /// Toggle the persistent literal-space mode (the `>` button): while on,
+    /// every command line behaves as if it started with `>` — Space stays in
+    /// the input instead of submitting. Saved in the user config.
+    CommandLiteralToggle,
     /// Copy the full command-line history (every line) to the system
     /// clipboard as plain text — issue #232, so output can be pasted for
     /// debugging instead of screenshotted.

src/app/settings.rs

@@ -112,6 +112,10 @@ pub struct UserSettings {
     /// Linked plugin source repositories (`owner/repo`) the marketplace installs
     /// from.
     pub plugin_repos: Vec<String>,
+    /// Command-line literal-space mode: when on, Space stays in the input
+    /// instead of submitting (as if every line started with `>`), until the
+    /// user toggles it back off.
+    pub literal_spaces: bool,
     /// Controls whether the TEXTEDIT command repeats automatically (0 = Multiple, 1 = Single).
     pub texteditmode: bool,
     /// TEXTFILL: fill TrueType glyphs (true) or draw them hollow (false).
@@ -143,6 +147,7 @@ impl Default for UserSettings {
             default_assoc_prompted: false,
             disabled_plugins: Vec::new(),
             plugin_repos: Vec::new(),
+            literal_spaces: false,
             texteditmode: false,
             textfill: true,
             backup_on_save: true,

src/app/update/file.rs

@@ -75,6 +75,7 @@ impl OpenCADStudio {
                 v
             },
             plugin_repos: self.plugin_repos.clone(),
+            literal_spaces: self.command_line.literal_spaces,
             texteditmode: self.texteditmode,
             textfill: crate::scene::text::sdf_atlas::textfill(),
             backup_on_save: self.backup_on_save,
@@ -96,6 +97,7 @@ impl OpenCADStudio {
         self.default_assoc_prompted = s.default_assoc_prompted;
         self.disabled_plugins = s.disabled_plugins.iter().cloned().collect();
         self.plugin_repos = s.plugin_repos.clone();
+        self.command_line.literal_spaces = s.literal_spaces;
         self.texteditmode = s.texteditmode;
         crate::scene::text::sdf_atlas::set_textfill(s.textfill);
         self.backup_on_save = s.backup_on_save;

src/app/update/mod.rs

@@ -770,7 +770,7 @@ impl OpenCADStudio {
                 // the submit path, which tokenises multi-token lines — so a typed
                 // token, a pasted `LINE 0,0 10,10`, or API-fed text all run their
                 // spaces as step separators. A leading `>` keeps spaces literal.
-                if !s.starts_with('>') && s.contains(' ') {
+                if !self.command_line.literal_spaces && !s.starts_with('>') && s.contains(' ') {
                     self.command_line.input = s;
                     return self.update(Message::CommandSubmit);
                 }
@@ -856,6 +856,12 @@ impl OpenCADStudio {
                 Task::none()
             }
 
+            Message::CommandLiteralToggle => {
+                self.command_line.literal_spaces = !self.command_line.literal_spaces;
+                self.save_config();
+                self.focus_cmd_input()
+            }
+
             Message::CommandHistoryToggle => {
                 self.command_line.toggle_history();
                 // On open, snapshot the current log into the read-only editor
@@ -924,10 +930,11 @@ impl OpenCADStudio {
                     self.mtext_type(" ");
                     return Task::none();
                 }
-                // A leading `>` puts the command line in "literal space" mode so
-                // the user can type arguments that contain spaces; otherwise
-                // Space works like Enter. The `>` is stripped on submit.
-                if self.command_line.input.starts_with('>') {
+                // A leading `>` (or the persistent `>` toggle) puts the command
+                // line in "literal space" mode so the user can type arguments
+                // that contain spaces; otherwise Space works like Enter. The
+                // typed `>` is stripped on submit.
+                if self.command_line.literal_spaces || self.command_line.input.starts_with('>') {
                     self.command_line.input.push(' ');
                     return Task::none();
                 }

src/ui/command_line.rs

@@ -5,7 +5,7 @@ use iced::time::Instant;
 use crate::app::Message;
 use crate::command::CmdOption;
 use iced::widget::{
-    button, column, container, opaque, row, text, text_editor, text_input, Space,
+    button, column, container, opaque, row, text, text_editor, text_input, tooltip, Space,
 };
 use iced::{Background, Border, Color, Element, Length, Theme};
 
@@ -27,6 +27,10 @@ const MAX_HISTORY: usize = 64;
 #[derive(Clone, Default)]
 pub struct CommandLine {
     pub input: String,
+    /// Persistent literal-space mode (the `>` toggle button): while on, every
+    /// line behaves as if it started with `>` — Space stays in the input
+    /// instead of submitting. Saved in the user config.
+    pub literal_spaces: bool,
     pub history: Vec<HistoryEntry>,
     /// Commands the user has typed (for ↑/↓ recall). Holds the raw typed
     /// strings so the line can be re-edited; distinct from `recent_commands`.
@@ -383,6 +387,64 @@ impl CommandLine {
                 }
             });
         let prompt = container(text("Command:").size(11).color(PROMPT_COLOR)).padding([5, 8]);
+        // Literal-space toggle: while active, every line behaves as if it
+        // started with `>` — Space stays in the line instead of submitting, so
+        // arguments with spaces (text strings, paths, `UCS Z 90` as one line)
+        // can be typed. Persists until toggled off; a hand-typed leading `>`
+        // lights the button too (same mode, one line only).
+        let literal_active = self.literal_spaces || self.input.starts_with('>');
+        let literal_btn = button(text(">").size(11).color(if literal_active {
+            Color::WHITE
+        } else {
+            PROMPT_COLOR
+        }))
+        .on_press(Message::CommandLiteralToggle)
+        .padding([2, 6])
+        .style(move |_: &Theme, status| {
+            let bg = if literal_active {
+                Color {
+                    r: 0.28,
+                    g: 0.40,
+                    b: 0.56,
+                    a: 1.0,
+                }
+            } else if matches!(status, button::Status::Hovered) {
+                Color {
+                    r: 0.22,
+                    g: 0.30,
+                    b: 0.42,
+                    a: 1.0,
+                }
+            } else {
+                INPUT_ROW_BG
+            };
+            button::Style {
+                background: Some(Background::Color(bg)),
+                text_color: Color::WHITE,
+                border: Border {
+                    color: BORDER_COLOR,
+                    width: 1.0,
+                    radius: 3.0.into(),
+                },
+                ..Default::default()
+            }
+        });
+        let literal_tip = container(
+            text("Literal spaces: Space stays in the line instead of running the command (same as typing a leading '>'). Stays on until toggled off.")
+                .size(11)
+                .color(Color::WHITE),
+        )
+        .padding([3, 6])
+        .style(|_: &Theme| container::Style {
+            background: Some(Background::Color(PANEL_BG)),
+            border: Border {
+                color: BORDER_COLOR,
+                width: 1.0,
+                radius: 3.0.into(),
+            },
+            ..Default::default()
+        });
+        let literal_btn = tooltip(literal_btn, literal_tip, tooltip::Position::Top).gap(4);
         // While dynamic input is capturing keystrokes, the command-line
         // text field is left without an `on_input` handler so it can't
         // grab focus or swallow numeric keys — those flow through the
@@ -509,7 +571,7 @@ impl CommandLine {
             ..Default::default()
         })
         .padding([2, 6]);
-        let input_row = row![prompt, input, dropdown_btn]
+        let input_row = row![prompt, literal_btn, input, dropdown_btn]
             .spacing(4)
             .align_y(iced::Center);