feat: add Report/About/Changelog buttons to Support ribbon group

- REPORT opens GitHub new-issue page
- ABOUT opens a dialog window with version, OS and arch info + Copy Info button
- CHANGELOG opens GitHub releases page
- Fix Windows build: add windows-sys as target-specific dependency for PRINT command

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/view.rs

@@ -96,6 +96,9 @@ impl H7CAD {
         if Some(window_id) == self.shortcuts_window {
             return crate::ui::shortcuts::view_window(&self.shortcut_overrides);
         }
+        if Some(window_id) == self.about_window {
+            return crate::ui::about::view_window();
+        }
 
         let i = self.active_tab;
         let tab = &self.tabs[i];