V48 (impl-only): Point Vercel at apps/uapi monorepo root

Encode monorepo install/build in apps/uapi/vercel.json and
document Root Directory apps/uapi for green deploys.

Author: geraldarthurdavis

.docs/VERCEL.md

@@ -75,7 +75,10 @@ Failure telemetry for sandbox create/run is surfaced through deposit pipeline UI
 ## 3. App deploy (`apps/uapi`)
 
 - Next.js App Router commercial site: packs, reads, deposits, docs, conversations, auxillaries, APIs.
-- Vercel project **Root Directory** must be `apps/uapi` after monorepo reorg.
+- Vercel project **Root Directory** = `apps/uapi` (required; monorepo layout).
+- In-repo deploy config: `apps/uapi/vercel.json`
+  - **Install:** monorepo root `pnpm install --frozen-lockfile` (workspace packages)
+  - **Build:** `pnpm run build` in `apps/uapi`
 - Serverless/edge constraints: force sandbox host on serverless; LocalHost is local-only.
 
 Env of interest (non-exhaustive): public product flags, Supabase public keys,

apps/README.md

@@ -27,4 +27,6 @@ pnpm --dir apps/chatgpt test
 
 ## Vercel
 
-Set the Vercel project **Root Directory** to `apps/uapi` (was `uapi`).
+Project **Root Directory** must be `apps/uapi`. Monorepo install/build
+commands live in `apps/uapi/vercel.json` (install from repo root via pnpm
+workspace, then `pnpm run build` in the app).

apps/uapi/vercel.json

@@ -0,0 +1,11 @@
+{
+  "$schema": "https://openapi.vercel.sh/vercel.json",
+  "framework": "nextjs",
+  "installCommand": "cd ../.. && corepack enable && pnpm install --frozen-lockfile",
+  "buildCommand": "pnpm run build",
+  "build": {
+    "env": {
+      "NODE_VERSION": "22"
+    }
+  }
+}

vercel.json

@@ -1,4 +1,5 @@
 {
+  "$schema": "https://openapi.vercel.sh/vercel.json",
   "build": {
     "env": {
       "NODE_VERSION": "22"