feat: DDEDIT command and double-click text editing

Add DDEDIT (ED alias) command that edits Text/MText/Attribute entities
in-place via the command line. Double-clicking a text entity in model space
now auto-launches DDEDIT for that entity. Supports Text, MText,
AttributeDefinition, and AttributeEntity types.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

src/app/cmd_result.rs

@@ -619,6 +619,29 @@ impl H7CAD {
                 self.tabs[i].scene.clear_preview_wire();
                 self.restore_pre_cmd_tangent();
             }
+            CmdResult::DdeditEntity { handle, new_text } => {
+                let mut updated = false;
+                if let Some(entity) = self.tabs[i].scene.document.get_entity_mut(handle) {
+                    match entity {
+                        acadrust::EntityType::Text(t) => { t.value = new_text; updated = true; }
+                        acadrust::EntityType::MText(t) => { t.value = new_text; updated = true; }
+                        acadrust::EntityType::AttributeDefinition(a) => { a.default_value = new_text; updated = true; }
+                        acadrust::EntityType::AttributeEntity(a) => { a.set_value(new_text); updated = true; }
+                        _ => {}
+                    }
+                }
+                if updated {
+                    self.push_undo_snapshot(i, "DDEDIT");
+                    self.tabs[i].dirty = true;
+                    self.command_line.push_output("DDEDIT: text updated.");
+                } else {
+                    self.command_line.push_error("DDEDIT: entity type not supported.");
+                }
+                self.tabs[i].active_cmd = None;
+                self.tabs[i].snap_result = None;
+                self.tabs[i].scene.clear_preview_wire();
+                self.restore_pre_cmd_tangent();
+            }
         }
         // Focus the command-line input while a command is active; blur it when the command ends.
         if self.tabs[i].active_cmd.is_some() {

src/app/commands.rs

@@ -906,6 +906,28 @@ impl H7CAD {
                 self.tabs[i].active_cmd = Some(Box::new(new_cmd));
             }
 
+            "DDEDIT"|"ED" => {
+                use crate::modules::annotate::ddedit::{DdeditCommand, entity_text};
+                // If a single text/mtext entity is already selected, skip the pick step.
+                let sel = self.tabs[i].scene.selected_entities();
+                if sel.len() == 1 {
+                    let (h, _) = sel[0];
+                    if let Some(e) = self.tabs[i].scene.document.get_entity(h) {
+                        if let Some(cur) = entity_text(e) {
+                            let cmd = DdeditCommand::with_handle(h, cur.clone());
+                            self.command_line.push_info(&format!("DDEDIT  Enter new text <{cur}>:"));
+                            self.tabs[i].active_cmd = Some(Box::new(cmd));
+                        } else {
+                            self.command_line.push_error("DDEDIT: selected entity is not text.");
+                        }
+                    }
+                } else {
+                    let cmd = DdeditCommand::new();
+                    self.command_line.push_info(&cmd.prompt());
+                    self.tabs[i].active_cmd = Some(Box::new(cmd));
+                }
+            }
+
             "MTEXT"|"MT" => {
                 use crate::modules::annotate::mtext::MTextCommand;
                 let new_cmd = MTextCommand::new();

src/app/update.rs

@@ -1215,6 +1215,49 @@ impl H7CAD {
                     }
                 }
 
+                // ── Double-click in Model Space: DDEDIT for Text/MText ────
+                if is_click
+                    && is_down
+                    && self.tabs[i].active_cmd.is_none()
+                    && self.tabs[i].scene.current_layout == "Model"
+                {
+                    let now = Instant::now();
+                    let is_double_model = self
+                        .last_vp_click_time
+                        .map(|t| {
+                            let dt = now.duration_since(t).as_millis();
+                            let last = self.last_vp_click_pos.unwrap_or(p);
+                            let d = (p.x - last.x).hypot(p.y - last.y);
+                            dt < 400 && d < 8.0
+                        })
+                        .unwrap_or(false);
+
+                    self.last_vp_click_time = Some(now);
+                    self.last_vp_click_pos = Some(p);
+
+                    if is_double_model {
+                        let (vw, vh) = self.tabs[i].scene.selection.borrow().vp_size;
+                        let bounds = iced::Rectangle { x: 0.0, y: 0.0, width: vw, height: vh };
+                        let vp_mat = self.tabs[i].scene.camera.borrow().view_proj(bounds);
+                        let all_wires = self.tabs[i].scene.hit_test_wires();
+                        let hit = scene::hit_test::click_hit(p, &all_wires, vp_mat, bounds)
+                            .and_then(|s| Scene::handle_from_wire_name(s));
+                        if let Some(handle) = hit {
+                            if let Some(entity) = self.tabs[i].scene.document.get_entity(handle) {
+                                use crate::modules::annotate::ddedit::{DdeditCommand, entity_text};
+                                if let Some(cur) = entity_text(entity) {
+                                    let cmd = DdeditCommand::with_handle(handle, cur.clone());
+                                    self.command_line.push_info(
+                                        &format!("DDEDIT  Enter new text <{cur}>:")
+                                    );
+                                    self.tabs[i].active_cmd = Some(Box::new(cmd));
+                                    return self.focus_cmd_input();
+                                }
+                            }
+                        }
+                    }
+                }
+
                 // ── Double-click: enter/exit MSPACE ───────────────────────
                 // Only when no command is running, no drag, and we're in paper space.
                 if is_click