docs: change configurations to make v2 the main docs (#9729)

* docs: change configurations to make v2 the main docs

* move api routes to top level

* remove api prefix

* update opengraph images

* show v1 link

* add redirect to v1

www/apps/api-reference/app/download/[area]/route.ts

@@ -0,0 +1,29 @@
+import { existsSync, readFileSync } from "fs"
+import { NextResponse } from "next/server"
+import path from "path"
+
+type DownloadParams = {
+  params: {
+    area: string
+  }
+}
+
+export function GET(request: Request, { params }: DownloadParams) {
+  const { area } = params
+  const filePath = path.join(process.cwd(), "specs", area, "openapi.full.yaml")
+
+  if (!existsSync(filePath)) {
+    return new NextResponse(null, {
+      status: 404,
+    })
+  }
+
+  const fileContent = readFileSync(filePath)
+
+  return new Response(fileContent, {
+    headers: {
+      "Content-Type": "application/x-yaml",
+      "Content-Disposition": `attachment; filename="openapi.yaml"`,
+    },
+  })
+}