Add a decimals option, fix dropdown overflow and the texture filter

- NumberField takes a decimals option (default 3); frame rects and the
  slice dialog use 0, matching their integer model.
- Button truncates its label to the drawn width; Dropdown reserves the
  chevron slot. NodeView reuses the shared truncate().
- Setting scaleMode leaves the style's shared resource id in place, so
  the old GPU sampler stayed in use until a reload. Call style.update().
- Graph gets a header bar like the Texture tab: GraphEditor is now the
  frame, the former editor is GraphCanvas. A selection the tab does not
  concern no longer unloads the behavior.
- New e2e step 14 guards text overflow across all widgets.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/editor/debugHook.ts

@@ -50,6 +50,42 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
     walk(ui().overlay);
     return out;
   };
+  /**
+   * Visible texts drawn wider than the widget that owns them – the shape of bug where a label
+   * runs past its own control instead of being shortened to fit.
+   *
+   * The owner's box is its declared `w`/`h` at its global position, NOT `getBounds()`: a Pixi
+   * container has no size of its own, so its bounds are the union of its children – including
+   * the very text that overflows, which makes every overflow measure as zero. Texts inside a
+   * scroll container are skipped, where sticking out is the point and the mask hides it.
+   */
+  const textOverflows = (all = false): { text: string; owner: string; over: number }[] => {
+    const out: { text: string; owner: string; over: number }[] = [];
+    const walk = (node: Container, owner: Widget | null, clipped: boolean): void => {
+      if (!node.visible) return;
+      const isWidget = node instanceof Widget;
+      const box = isWidget ? node : owner;
+      // A mask further up – a panel clipping its contents – does not excuse a label spilling
+      // out of its own control, so the question restarts at every widget. Only a mask at or
+      // below the owner (a text field's scroll window, a scroll container) makes it intended.
+      // `Boolean`, not `!== null`: Pixi's mask getter returns `undefined` when nothing masks,
+      // so comparing against null marks every container as clipped and hides every finding.
+      const masked = (isWidget ? false : clipped) || Boolean(node.mask);
+      if (node instanceof Text) {
+        if (!box || !node.text || (masked && !all)) return;
+        const text = node.getBounds();
+        const origin = box.getGlobalPosition();
+        const over = Math.max(text.x + text.width - (origin.x + box.w), origin.x - text.x);
+        if (over > 1 || all) {
+          out.push({ text: node.text, owner: box.constructor.name, over: Math.round(over) });
+        }
+        return;
+      }
+      for (const child of node.children) walk(child, box, masked);
+    };
+    walk(app.stage, null, false);
+    return out;
+  };
   /** Screen rectangle of the open popup (the backdrop is not a widget), or null when none is. */
   const overlayRect = (): { x: number; y: number; w: number; h: number } | null => {
     const popups = ui().overlay.children.filter((node): node is Widget => node instanceof Widget);
@@ -63,6 +99,7 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
     locate,
     overlayTexts,
     overlayRect,
+    textOverflows,
     viewportCenter: () => centreOf(viewport),
     viewportInfo: () => viewport.debugInfo(),
     gameInfo: () => gameView.debugInfo(),
@@ -77,9 +114,11 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
     graph: {
       current: () => graphEditor.currentAssetId,
       portAt: (nodeId: string, port: string, isOutput: boolean) =>
-        graphEditor.portGlobal(nodeId, port, isOutput),
-      nodeAt: (nodeId: string) => graphEditor.nodeGlobal(nodeId),
-      center: () => centreOf(graphEditor),
+        graphEditor.canvas.portGlobal(nodeId, port, isOutput),
+      nodeAt: (nodeId: string) => graphEditor.canvas.nodeGlobal(nodeId),
+      // The canvas, not the whole tab: a point measured through the header would sit above
+      // the drawing area a right-click test aims at.
+      center: () => centreOf(graphEditor.canvas),
     },
     texture: {
       current: () => textureEditor.currentAssetId,