feat(input): scalar entry via dynamic input

Text-input steps (OFFSET distance, POLYGON sides, radii, counts) were
swallowed by the dynamic-input overlay: typed digits landed in the field
buffer and Enter committed a point pick, so the value never reached
on_text_input (issue #61). Now each text step shows one scalar box whose
value routes to on_text_input on commit; non-numeric prompts (names,
keywords) keep going to the command line so mixed text like "Bolt12"
isn't split.

OFFSET reworked: object first, then through-mode by default — the offset
follows the cursor at the perpendicular distance to the object. Typing a
number locks the magnitude (cursor then only picks the side); a value
typed and clicked without Enter is applied before the point pick.

The dynamic-input overlay and the command line now show the active
step's prompt and hold it until the step completes.

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

src/ui/command_line.rs

@@ -226,7 +226,12 @@ impl CommandLine {
         matches
     }
 
-    pub fn view(&self, show_autocomplete: bool, dyn_capturing: bool) -> Element<'_, Message> {
+    pub fn view(
+        &self,
+        show_autocomplete: bool,
+        dyn_capturing: bool,
+        active_prompt: Option<String>,
+    ) -> Element<'_, Message> {
         // Only the most recent entries pushed within the last few
         // seconds show on the overlay. The dropdown button keeps the
         // full backlog reachable when the user actually wants it.
@@ -247,7 +252,12 @@ impl CommandLine {
                 };
                 col.push(container(text(&entry.text).size(11).color(color)).padding([1, 8]))
             });
-        let prompt = container(text("Command:").size(11).color(PROMPT_COLOR)).padding([5, 8]);
+        // While a command is running, the prompt shows what the current
+        // step is asking for and stays put until that step completes — it
+        // does not fade like the history lines. With no active command it
+        // falls back to the generic entry prompt.
+        let prompt_label = active_prompt.unwrap_or_else(|| "Command:".to_string());
+        let prompt = container(text(prompt_label).size(11).color(PROMPT_COLOR)).padding([5, 8]);
         // 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

src/ui/overlay.rs

@@ -1188,10 +1188,15 @@ pub struct DynBox {
     pub locked: bool,
 }
 
-pub fn dynamic_input_overlay<'a>(cursor_screen: Point, boxes: Vec<DynBox>) -> Element<'a, Message> {
+pub fn dynamic_input_overlay<'a>(
+    cursor_screen: Point,
+    boxes: Vec<DynBox>,
+    prompt: String,
+) -> Element<'a, Message> {
     canvas(DynInputCanvas {
         cursor_screen,
         boxes,
+        prompt,
     })
     .width(Length::Fill)
     .height(Length::Fill)
@@ -1201,6 +1206,9 @@ pub fn dynamic_input_overlay<'a>(cursor_screen: Point, boxes: Vec<DynBox>) -> El
 struct DynInputCanvas {
     cursor_screen: Point,
     boxes: Vec<DynBox>,
+    /// The active command's current prompt — tells the user what this step
+    /// is asking for, drawn just above the input boxes.
+    prompt: String,
 }
 
 impl canvas::Program<Message> for DynInputCanvas {
@@ -1258,6 +1266,31 @@ impl canvas::Program<Message> for DynInputCanvas {
             by = (self.cursor_screen.y - BOX_H - 4.0).max(0.0);
         }
 
+        // Prompt line above the boxes — what this step wants right now.
+        // Drawn on an opaque pill so the viewport behind it stays legible.
+        if !self.prompt.is_empty() {
+            let py = (by - BOX_H - 2.0).max(0.0);
+            let pw = (self.prompt.len() as f32 * CHAR_W) + PAD * 2.0;
+            let prect = canvas::Path::rectangle(
+                Point { x: bx, y: py },
+                Size { width: pw, height: BOX_H },
+            );
+            frame.fill(&prect, Color { r: 0.10, g: 0.10, b: 0.12, a: 1.0 });
+            frame.stroke(
+                &prect,
+                canvas::Stroke::default()
+                    .with_color(Color { r: 0.35, g: 0.55, b: 0.90, a: 0.9 })
+                    .with_width(1.0),
+            );
+            frame.fill_text(canvas::Text {
+                content: self.prompt.clone(),
+                position: Point { x: bx + PAD, y: py + PAD },
+                color: Color { r: 0.70, g: 0.85, b: 0.70, a: 1.0 },
+                size: iced::Pixels(FONT_SIZE),
+                ..Default::default()
+            });
+        }
+
         let mut x = bx;
         for (i, b) in self.boxes.iter().enumerate() {
             let w = widths[i];