fix(tui): bundle React-rendering deps so a consumer install can't split React

`ink-form` and `ink-scroll-view` were externalized by the TUI bundler and
both declare a loose `react` peer (">=18"). Installed under a project that
has its own React 18, npm hoists them to that project's root — where the
peer is satisfied — while the Inspector's React 19 nests underneath. The
bundle then renders through React 19 while those two call hooks on React
18, whose dispatcher is null, so opening a tool test form (or any scroll
view) dies with "Cannot read properties of null (reading 'useState')".

Inline them instead: their `import "react"` is emitted into the bundle and
so resolves from the build directory exactly like the bundle's own, with
npm's placement no longer part of the decision. This also pins their
transitive deps to what this repo resolved — notably `ink-select-input@6`
via `overrides`, which npm ignores for a package installed as a dependency,
so consumers were getting the React-18-era v5.

`ink` stays external: it can't be bundled (its CJS `signal-exit@3` fails
ESM interop with `Dynamic require of "assert"`) and doesn't need to be —
its ">=19" peer keeps npm from hoisting it next to an unusable React.

Both packages are dropped from the root `dependencies`, since the tarball
now ships their code rather than having consumers install them.

`clients/tui/__tests__/tsupConfig.test.ts` is the durable guard: the
failure is invisible in this repo and in every smoke (a dev install has
one React) and only appears once the package is installed under another
project, so the invariant is asserted against the config instead — every
dependency declaring a `react` peer must be bundled unless exempted.

Closes #1952

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WLYmVPVLdeYpE6aMTUsCks

README.md

@@ -310,6 +310,7 @@ The root `package.json` `"files"` allowlist is the source of truth for the tarba
 - **No source maps.** The client bundlers set `sourcemap: false` (`clients/{cli,tui}/tsup.config.ts`, `clients/web/tsup.runner.config.ts`); Vite and the launcher's `tsc` already emit none. Maps are ~half the unpacked size and aren't needed at runtime — debug via `npm run dev` on the source.
 - **`clients/web/build` ships via `clients/web/.npmignore`.** `clients/web/.gitignore` lists `build/`, and npm's packlist honors that nested `.gitignore` over the root `"files"` allowlist — so the prod web-server runner was silently missing from the tarball while `clients/web/dist` slipped through (its `.gitignore` only lists `dist-ssr`). `clients/web/.npmignore` overrides the `.gitignore` for publishing so both `build/` (runner) and `dist/` (SPA) ship. The other clients don't need this — none ship a nested `.gitignore`.
 - **`clients/web/static` ships the MCP Apps sandbox proxy.** `clients/web/static/sandbox_proxy.html` is a committed source file (not a build artifact), read from disk at runtime by `clients/web/server/sandbox-controller.ts` as `<runner dir>/../static/sandbox_proxy.html`. It was missing from the root `"files"` allowlist entirely, so every published build failed the Apps tab with **"Sandbox not loaded"** ([#1859](https://github.com/modelcontextprotocol/inspector/issues/1859)) while working fine in the repo. Because the path is resolved _relative to_ `clients/web/build`, the directory must ship at that exact location — `pack:verify` asserts both the tarball entry and the installed-on-disk path.
+- **A dependency that renders React is bundled, not externalized.** An externalized package resolves its own `react` from wherever npm placed **it** in the consumer's tree, which is not necessarily where the bundle resolves ours. `ink-form` and `ink-scroll-view` declare a loose `react` peer (`">=18"`), so a project holding React 18 satisfies them and hoists them to its own root while the Inspector's React 19 nests underneath — two React copies, and the TUI dies with `TypeError: Cannot read properties of null (reading 'useState')` the moment a tool test form or a scroll view mounts ([#1952](https://github.com/modelcontextprotocol/inspector/issues/1952)). Both are therefore inlined by `clients/tui/tsup.config.ts` and are **not** root dependencies: the tarball ships their code inside `clients/tui/build/index.js` rather than having consumers install them. Bundling also pins their transitive deps to what this repo's install resolved (notably `ink-select-input@6` via `overrides`, which npm ignores for a package installed as a dependency). `ink` is the one React renderer left external — it can't be bundled (CJS `signal-exit@3` fails ESM interop) and its `">=19"` peer keeps npm from misplacing it. `clients/tui/__tests__/tsupConfig.test.ts` guards the split; see the [TUI README](./clients/tui/README.md#bundling-react-rendering-dependencies-must-be-inlined-1952).
 - **A single version number, read from the root `package.json`.** The Inspector ships as one package with one version, so only the **root** `package.json` carries a `version` — the four `clients/*/package.json`s deliberately have none. Every Node client (CLI, TUI, and the web backend) resolves the version through the shared `readInspectorVersion()` reader in `core/node/version.ts`, which walks up to the root manifest (always present in the tarball). No client `package.json` is read at runtime, so none needs to ship. The web **browser** can't read the filesystem; it gets its version from the backend via `GET /api/config` (see [#1639](https://github.com/modelcontextprotocol/inspector/issues/1639)).
 
 ### `npm run pack:verify` — publish smoke against the real tarball