refactor: migrate TrumpSignal to TypeScript monorepo and Pages Router

apps/web/pages/api/proxy/[...path].ts

@@ -0,0 +1,49 @@
+import type { NextApiRequest, NextApiResponse } from 'next'
+export const config = { api: { bodyParser: false, responseLimit: '8mb' } }
+export default async function handler(req: NextApiRequest, res: NextApiResponse) {
+  const path = req.query.path
+  if (!Array.isArray(path) || path.some((p) => p === '..' || p.includes('/') || p.includes('\\')))
+    return res.status(400).json({ error: 'Invalid path' })
+  const base = process.env.API_URL || process.env.NEXT_PUBLIC_API_URL || 'http://localhost:8000'
+  const target = new URL('/' + path.map(encodeURIComponent).join('/'), base)
+  const incoming = new URL(req.url ?? '/', 'http://localhost')
+  target.search = incoming.search
+  const headers = new Headers()
+  const hop = new Set([
+    'host',
+    'connection',
+    'transfer-encoding',
+    'content-length',
+    'keep-alive',
+    'upgrade',
+    'x-forwarded-host',
+    'x-forwarded-proto',
+  ])
+  for (const [k, v] of Object.entries(req.headers))
+    if (v && !hop.has(k)) headers.set(k, Array.isArray(v) ? v.join(',') : v)
+  headers.set('accept-encoding', 'identity')
+  try {
+    const chunks: Buffer[] = []
+    let bytes = 0
+    for await (const chunk of req) {
+      const b = Buffer.from(chunk)
+      bytes += b.length
+      if (bytes > 1024 * 1024) return res.status(413).end()
+      chunks.push(b)
+    }
+    const body = req.method === 'GET' || req.method === 'HEAD' ? undefined : Buffer.concat(chunks)
+    const upstream = await fetch(target, {
+      method: req.method,
+      headers,
+      body,
+      signal: AbortSignal.timeout(30_000),
+      redirect: 'manual',
+    })
+    upstream.headers.forEach((v, k) => {
+      if (!hop.has(k) && k !== 'content-encoding') res.setHeader(k, v)
+    })
+    res.status(upstream.status).send(Buffer.from(await upstream.arrayBuffer()))
+  } catch {
+    res.status(502).json({ error: 'Upstream request failed' })
+  }
+}