**Stack 1/6** of the TanStack Start migration (#46424), split into
reviewable, independently-mergeable PRs.
> [!IMPORTANT]
> **Next stays the default and only active framework after this PR.**
This wires up the Vite/TanStack-Start build pipeline behind the
`STUDIO_FRAMEWORK` flag, but there are no TanStack routes yet — so the
TanStack build isn't functional or tested until later PRs in the stack.
Nothing about the Next build, dev, or deploy changes behaviourally here.
## What's in this PR
- **Dispatch:** `dev`/`build`/`start` now go through
`scripts/dispatch.js`, which runs the Next variant unless
`STUDIO_FRAMEWORK=tanstack`. The original commands are preserved as
`dev:next`/`build:next`/`start:next`.
- **Build pipeline:** `vite.config.ts`, `serve.js`, `smoke-server.mjs`,
vite/tanstack deps, `turbo.jsonc`.
- **`tsconfig.json`:** `jsx: react-jsx`, `moduleResolution: Bundler`,
`target: ES2022`. Because `include` is `**/*.ts(x)`, this re-typechecks
the whole app, so the companion adaptations below land with it.
- **Shared adaptations (companions to the tsconfig change):**
`BufferSource` casts, `packages/ui` unused-`React` import removals, etc.
- **Routing/middleware plumbing:** `next.config.ts` +
`redirects.shared.ts` (redirect rules now shared with `vercel.ts`),
`proxy.ts`/`start.ts` middleware + `hosted-api-allowlist.ts`.
## Verification
Run locally off `master`: frozen install ✓, `studio` typecheck ✓, **Next
build ✓** (compiles + generates all routes), lint ratchet ✓ ("some rules
improved"), prettier ✓.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Added a hosted API endpoint allowlist to return 404 for non-supported
`/api/*` routes.
* Introduced a TanStack route-migration checklist and expanded TanStack
Start routing support.
* **Improvements**
* Enhanced deployment refresh/detection by tightening cookie handling
for “latest deployment” updates.
* Centralized redirect/maintenance-mode rules for consistent platform vs
self-hosted behavior.
* Improved production serving with a dedicated static + proxy server and
a post-build smoke test.
* **Dependencies**
* Updated TanStack-related packages and React Table/query tooling
versions.
* **Documentation / Chores**
* Updated formatting and tooling config; added shared build environment
parsing utilities.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Alaister Young <[email protected]>
Co-authored-by: Ivan Vasilov <[email protected]>