refactor(apps)!: delete web-tanstack demo app

Veect retrofit (ADR-027): the product is a hosted SaaS built on
web-next; apps/web-tanstack existed only as template demo surface for
the TanStack Start framework path. This slice removes the app and all
wiring that referenced it:

- turbo.json globalEnv: WEB_TANSTACK_SENTRY_DSN,
  VITE_WEB_TANSTACK_SENTRY_DSN, VITE_GIT_COMMIT_SHA,
  SENTRY_PROJECT_WEB_TANSTACK
- .env.example: the same four DSN/release vars
- generator e2e fixtures that stripped deps from the app's package.json
- coverage diff comment + test fixtures referencing apps/web-tanstack
- app-list entries in README, CLAUDE.md (port table, Sentry projects),
  AGENTS.md (tags, binder list, per-app docs), docs/glossary.md (App)
- pnpm-lock.yaml importer + orphaned transitive deps

Framework-support code in core packages stays: core-trpc's TanStack
provider, core-shared security/tanstack middleware, and the Sentry
react/node init adapters are generic TanStack support, not app wiring.
Prose in guides/ADRs/library traces is story 08 scope.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016j8z4VHjedXDTjEDNg7qHK

scripts/coverage/diff.test.mjs

@@ -246,15 +246,12 @@ describe("computeDiffCoverage", () => {
   test("skips apps/ files (app packages don't configure @vitest/coverage-v8)", () => {
     const lcov = parseLcov(lcovText);
     const diff = new Map([
-      // web-next and web-tanstack have no @vitest/coverage-v8 — never in lcov
+      // web-next and cms have no @vitest/coverage-v8 — never in lcov
       ["apps/web-next/instrumentation-client.ts", new Set([1, 2, 3, 4, 5, 6])],
       ["apps/web-next/middleware.ts", new Set([1, 2, 3, 4, 5])],
       ["apps/web-next/src/app/layout.tsx", new Set([1, 2, 3])],
-      [
-        "apps/web-tanstack/src/instrumentation-client.ts",
-        new Set([1, 2, 3, 4, 5]),
-      ],
-      ["apps/web-tanstack/app.config.ts", new Set([1, 2, 3])],
+      ["apps/cms/src/instrumentation.ts", new Set([1, 2, 3, 4, 5])],
+      ["apps/cms/src/payload.config.ts", new Set([1, 2, 3])],
     ]);
     const result = computeDiffCoverage(diff, lcov);
     assert.equal(result.status, "pass");