Shaders draw in the sprite's own pass: a Mesh with the graph's fragment, no filter (#77)

A sprite's picture is now a Mesh (unit quad, sibling of its Graphics node, which keeps
only the hit area); a worn shader replaces Pixi's fragment in that draw, so there is no
intermediate texture and no extra render pass. Measured on the HD 630: 400 shaded
sprites hold 60 fps (was 34), 800 hold 56 (was 20).

Two Pixi facts the code leans on: a mesh's texture is bound only for Pixi's own shader,
so GraphShader.wear hands it over; and MeshPipe caches whether a mesh batches and
re-checks it only in a frame without structure changes, so switching a shader on or
off calls mesh.unload().

The console panel mirrors console.group/groupCollapsed/groupEnd and fills the %s %d
%o %c directives, so Pixi's deprecation warning shows its head, not only its stack.
E2E 12 guards against the addChild-on-Graphics warning, 28 counts shaders instead of
filters.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/editor/debugHook.ts

@@ -1,4 +1,4 @@
-import { type Application, Color, type ColorSource, type Container, Rectangle, Text } from 'pixi.js';
+import { type Application, Color, type ColorSource, type Container, Mesh, Rectangle, Text } from 'pixi.js';
 import { resolveObjects } from '../core/model/instance';
 import { findObjectHolder } from '../core/model/Project';
 import type { FrameRect } from '../core/model/texture';
@@ -171,6 +171,8 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
   };
   (window as unknown as { __gm: unknown }).__gm = {
     state,
+    /** The Pixi application, for probes that need the renderer or the stage. */
+    app,
     sceneObjects: () => (state.activeScene ? objectsOf(state.activeScene.id) : []),
     locate,
     locateAll,
@@ -386,7 +388,7 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
       };
     },
     fps: () => editor.fps,
-    /** Visible nodes carrying a filter – one extra render pass each, which is what shader cost is made of. */
+    /** Visible nodes carrying a filter – one extra render pass each; since #77 a shader is none. */
     filterCount: () => {
       let n = 0;
       const walk = (node: Container): void => {
@@ -397,6 +399,17 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
       walk(app.stage);
       return n;
     },
+    /** Visible sprite meshes drawing with a shader of their own – one draw call each, no pass (#77). */
+    shaderCount: () => {
+      let n = 0;
+      const walk = (node: Container): void => {
+        if (!node.visible) return;
+        if (node instanceof Mesh && node.shader) n += 1;
+        for (const child of node.children) walk(child);
+      };
+      walk(app.stage);
+      return n;
+    },
     lowLatency: () =>
       (app.renderer as unknown as { gl?: WebGL2RenderingContext }).gl?.getContextAttributes()
         ?.desynchronized === true,