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>

web/tests/unit/library-path-normalization.test.mjs

@@ -6,6 +6,7 @@ import path from "node:path";
 import { pathToFileURL } from "node:url";
 import test from "node:test";
 import ts from "typescript";
+import { assertLegacyManifestArtifacts } from "./legacy-manifest-integrity.mjs";
 
 const root = path.resolve(import.meta.dirname, "../../..");
 const temporary = fs.mkdtempSync(path.join(os.tmpdir(), "library-path-normalization-unit-"));
@@ -28,7 +29,7 @@ const policy = { schemaVersion: 1, declaredHttpsOrigins: ["https://assets.exampl
 test("M12-04B binds the shared path normalizer and evidence artifacts", () => {
   assert.equal(manifest.task, "M12-04B");
   assert.equal(manifest.nextTask, "M12-04C");
-  for (const artifact of Object.values(manifest.artifacts)) assert.equal(sha256(artifact.path), artifact.sha256, artifact.path);
+  assertLegacyManifestArtifacts(manifest);
 });
 
 test("M12-04B canonicalizes POSIX and Windows separators with dot segments", () => {