fix: text editor selection, styling, and script coverage

Clears the previous document before opening a new one, keeps the
selection when clicking the dock or rotating a box, refreshes the glass
overlay so style changes preview every time, adds double-click word
selection, and widens the Windows font stacks for Indic scripts. The
dock now publishes its own height so the swatches lay out correctly on
small screens.

src/js/logic/edit-pdf-text-dock.ts

@@ -729,6 +729,15 @@ export function setupFormatDock(): void {
     updateOffset();
   }
 
+  const publishDockHeight = () => {
+    app.style.setProperty(
+      '--ecdock',
+      `${Math.round(inspector.getBoundingClientRect().height)}px`
+    );
+  };
+  new ResizeObserver(publishDockHeight).observe(inspector);
+  publishDockHeight();
+
   setupPagePill();
   refresh();
 }