feat(plot): QUICKPRINT/QP — plot a selection's bounding box to PDF (#325)

Run QUICKPRINT (or QP), select objects, then Enter: the selection's
bounding box becomes the plot window and a PDF is written next to the
drawing (<name>_<timestamp>.pdf) using the active page setup, with no
dialog. Model space.

Implemented as a selection-gathering CadCommand (src/modules/view/
quick_print.rs) returning CmdResult::QuickPrint(handles); the host
(on_quick_print_handles) unions the picked entities' AABBs, sets the
plot window, and reuses the tested clipped window-export path.

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

src/app/commands/dim.rs

@@ -654,6 +654,13 @@ impl OpenCADStudio {
                 self.tabs[i].active_cmd = Some(Box::new(cmd));
             }
 
+            "QUICKPRINT" | "QP" => {
+                use crate::modules::view::quick_print::QuickPrintCommand;
+                let cmd = QuickPrintCommand::new();
+                self.command_line.push_info(&cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(cmd));
+            }
+
             // Bare ZOOM enters the interactive window zoom (pick two corners) —
             // the common "zoom to a rectangle" action. The sub-keyword forms
             // (ZOOM EXTENTS / IN / OUT / …) are matched above.

src/app/commands/mod.rs

@@ -512,6 +512,8 @@ inventory::submit!(crate::command::CommandRegistration {
         "PROPS",
         "PSPACE",
         "PURGE",
+        "QP",
+        "QUICKPRINT",
         "QS",
         "QSAVE",
         "QSELECT",