chore: checkpoint web Blender migration source, tools and docs

Accumulated uncommitted work: GHOST Web backend, WebGL/GPU web layer,
web workflow engine and protocol, tooling, docs and task records.
Large generated evidence, user-testing archives, build snapshots and
imported test assets remain untracked.

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

tools/web/.probe55.mjs

@@ -0,0 +1,31 @@
+import { createRequire } from "node:module";
+import path from "node:path";
+const { chromium } = createRequire(import.meta.url)(path.resolve("web/node_modules/playwright"));
+const browser = await chromium.launch({ headless: true, executablePath: "/usr/bin/google-chrome-stable",
+  args: ["--no-sandbox","--use-gl=swiftshader","--enable-unsafe-swiftshader","--enable-unsafe-webgpu","--enable-dawn-features=allow_unsafe_apis","--use-webgpu-adapter=swiftshader"] });
+const ctx = await browser.newContext({ viewport: { width: 1440, height: 900 } });
+const page = await ctx.newPage();
+await page.addInitScript(() => {
+  const reg = []; window.__w = reg;
+  window.Worker = new Proxy(window.Worker, { construct(t, a) { const w = Reflect.construct(t, a); reg.push({ url: String(a[0]), worker: w }); return w; } });
+});
+await page.goto("http://127.0.0.1:5412/", { waitUntil: "domcontentloaded" });
+await page.waitForFunction(() => document.body.innerText.includes("WASM ABI: ready"), undefined, { timeout: 120000 });
+await page.getByTestId("blend-file-input").setInputFiles(path.resolve("tests/files/web/hierarchy_simplify_combined.blend"));
+await page.waitForFunction(() => /SceneIR r\d+/.test(document.querySelector('[data-testid="engine-status"]')?.textContent ?? ""), undefined, { timeout: 120000 });
+await page.waitForTimeout(4000);
+const snap = await page.evaluate(() => new Promise((resolve, reject) => {
+  const worker = window.__w.find(x => /web-engine\.worker/.test(x.url))?.worker;
+  if (!worker) return reject(new Error('no engine'));
+  const requestId = 'p-' + Math.random();
+  const timer = setTimeout(() => reject(new Error('timeout')), 30000);
+  const recv = ({ data }) => { if (data.requestId === requestId) { clearTimeout(timer); window.removeEventListener('message', recv); resolve(data); } };
+  worker.addEventListener('message', recv);
+  worker.postMessage({ requestId, command: { type: 'snapshot' } });
+}));
+const wf = snap.result?.snapshot?.editorWorkflow;
+console.log("STATUS", wf?.status ?? "none");
+for (const ws of (wf?.workspaces ?? []).slice(0, 3)) {
+  console.log("WS", ws.name, JSON.stringify(ws.areas.map(a => ({ e: a.editor, r: a.rect, active: a.id === ws.activeAreaId }))));
+}
+await browser.close();