chore(tooling): port upstream infra/tooling audit fixes

Ports the kept-file portions of the upstream infra audit-fix subset onto
the clean-slate template branch (auth-only shape; workspaces feature never
existed here, so its package.json edit is skipped):

- resolve the root playwright config in pnpm test:visual (S8)
- prune dead VERCEL_ENV from turbo.json globalEnv (S9)
- drop the duplicate chromium install in the storybook CI job (S10)
- wire scripts/**/*.test.mjs under a dedicated vitest runner
  (vitest.scripts.config.mjs + pnpm test:scripts + CI validate step);
  convert node:test imports to vitest keeping node:assert
- ignore *.tsbuildinfo repo-wide and untrack the committed build state
- align every @trpc/* range on ^11.18.0 so the workspace resolves to a
  single version (peer-warning-free install)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016j8z4VHjedXDTjEDNg7qHK

scripts/work/state-builder.test.mjs

@@ -12,7 +12,8 @@ import {
 function makeWorkTree({ epics }) {
   const root = fs.mkdtempSync(path.join(os.tmpdir(), "work-state-"));
   for (const [epicId, epicData] of Object.entries(epics)) {
-    const epicDir = path.join(root, epicId);
+    // buildState walks <workRoot>/epics/ — mirror the real docs/work layout.
+    const epicDir = path.join(root, "epics", epicId);
     fs.mkdirSync(epicDir, { recursive: true });
     fs.writeFileSync(
       path.join(epicDir, "_epic.md"),
@@ -85,6 +86,7 @@ describe("buildState", () => {
       epic1: {
         status: "in-progress",
         title: "epic1",
+        prd: null,
         stories: {
           story1: {
             status: "done",
@@ -127,7 +129,7 @@ describe("buildState", () => {
 
   it("parses depends-on and blocks frontmatter arrays", () => {
     const root = fs.mkdtempSync(path.join(os.tmpdir(), "work-dep-"));
-    const epicDir = path.join(root, "epic1");
+    const epicDir = path.join(root, "epics", "epic1");
     fs.mkdirSync(epicDir, { recursive: true });
     fs.writeFileSync(
       path.join(epicDir, "_epic.md"),