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>

api/index.php

@@ -39,7 +39,6 @@ function routeProjects(array $parts, string $method): never
 {
     $store = new Store(dirname(__DIR__) . '/data/projects');
 
-    // Collection: /projects
     if (count($parts) === 1) {
         if ($method === 'GET') {
             Response::json($store->list());
@@ -55,7 +54,6 @@ function routeProjects(array $parts, string $method): never
         Response::error('Method not allowed', 405);
     }
 
-    // Item: /projects/{id}
     $id = $parts[1];
     if (!Store::isValidId($id)) {
         Response::error('Invalid project id', 400);
@@ -100,7 +98,6 @@ function routeTextures(array $parts, string $method): never
 {
     $store = new TextureStore(dirname(__DIR__) . '/data/textures');
 
-    // Collection: /textures
     if (count($parts) === 1) {
         if ($method === 'GET') {
             Response::json($store->list());
@@ -119,7 +116,6 @@ function routeTextures(array $parts, string $method): never
         Response::error('Method not allowed', 405);
     }
 
-    // Item: /textures/{file}
     if ($method === 'DELETE') {
         if (!$store->delete($parts[1])) {
             Response::error('Texture not found', 404);