Refactor round: ship web/index.html, drop the remote browser, fix stale comments and README

- `.gitignore` said `index.html` unanchored, which also caught the Vite source page;
  a fresh clone could neither `dev` nor `build`. Anchored to `/index.html`, page added.
- Removed GM_REMOTE (tools/remote/gm-browser.ps1 and the ssh/scp branch in browser.mjs):
  the Windows test machine is gone and the only flaky check that lived on it is closed (#37).
- Removed `npm run preview`, undocumented and unused.
- Comments: wrong number in collider.test.ts (250 → 200), the "declarations used to…"
  history in listItems.ts and friends, the 24 px/28 contradiction, section banners in
  nodes/index.ts, node-catalog.test.ts and api/index.php, name paraphrases, and the stale
  step numbers in tools/e2e/11-…23- from the old global count.
- README: asset types include `animation`, kind order Number/Text/Boolean, tagged colour
  and texture items, 6/5 kinds, the `Texture` node, `./build.sh`, PROJECT_FORMAT_VERSION,
  and the file tree (kinds.ts, listItems.ts, propertyPorts.ts, Breadcrumb.ts, beads.ts,
  tools/assets/).
- tests/helpers.ts takes the duplicated `findObject` and `sceneWithCamera`.

Proof: ./check.sh 797 tests, full e2e ALL PASSED 633 checks against this bundle.

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

tools/e2e/13-frames.mjs

@@ -36,7 +36,7 @@ function nearestColour(sample) {
 export async function frames(t) {
   const { check, sleep, json, evaluate, shot, clickText, drag, press, undo } = t;
 
-  // 20. The tab exists and shows the texture the selection points at.
+  // 13a. The tab exists and shows the texture the selection points at.
   await press('Escape');
   await evaluate('__gm.state.select(null)');
   const texture = await json("(__gm.state.project.assets.find((a) => a.type === 'texture') ?? {}).id ?? ''");
@@ -51,7 +51,7 @@ export async function frames(t) {
   );
   await shot('33-texture-tab');
 
-  // 21. Dragging on the picture cuts a frame. Aimed at the top-right quadrant (32,0)-(64,24),
+  // 13b. Dragging on the picture cuts a frame. Aimed at the top-right quadrant (32,0)-(64,24),
   //     inset by a pixel: a press on a frame edge is read as a resize, not a new rectangle.
   const from = await json('__gm.texture.pointAt(33, 1)');
   const to = await json('__gm.texture.pointAt(63, 23)');
@@ -81,7 +81,7 @@ export async function frames(t) {
   );
   await shot('34-frame-cut');
 
-  // 21a. It is one undo step, not one per pointer move.
+  // 13c. It is one undo step, not one per pointer move.
   await undo();
   await sleep(400);
   check(
@@ -93,7 +93,7 @@ export async function frames(t) {
   await t.redo();
   await sleep(400);
 
-  // 22. A sprite wearing the frame shows that part of the sheet and nothing else.
+  // 13d. A sprite wearing the frame shows that part of the sheet and nothing else.
   await evaluate(`(() => {
     const sprite = __gm.state.project.assets.find((a) => a.id === 'tex-sprite');
     sprite.props.color = 0xffffff;
@@ -120,7 +120,7 @@ export async function frames(t) {
     await shot('35-sprite-wearing-a-frame');
   }
 
-  // 23. Slicing offers a live count before it commits.
+  // 13e. Slicing offers a live count before it commits.
   // Repainted magenta first: magenta is nowhere in the sheet, so the fallback check below
   // cannot be confused with a part of the picture.
   await evaluate(`(() => {
@@ -156,7 +156,7 @@ export async function frames(t) {
   check('and numbers them in reading order', sliced[0]?.startsWith('Frame 1 '), JSON.stringify(sliced[0]));
   await shot('36-sliced-sheet');
 
-  // 23a. A sprite pointed at a frame slicing removed falls back to its colour.
+  // 13f. A sprite pointed at a frame slicing removed falls back to its colour.
   await evaluate("__gm.showTab('scene')");
   await sleep(700);
   if (box) {