refactor(executor): switch vercel template from Next.js to Deno runtime

- Replace Next.js app router with pure Deno API functions
- Use vercel-deno@3.0.0 community runtime for native HTTP imports
- Deno natively supports importing from esm.sh URLs
- Simplified template: just api/health.ts and api/execute-tool.ts
- Remove unnecessary React/Next.js dependencies
- Update README with new architecture documentation

This matches the Railway executor's Deno-based approach but runs on
the user's own Vercel account. The Deno runtime enables dynamic
imports from esm.sh without any special setup.

templates/vercel-executor/app/api/execute-tool/route.ts

@@ -1,112 +0,0 @@
-/**
- * Execute Tool Endpoint
- *
- * POST /api/execute-tool
- * Executes a TPMJS tool with the provided parameters
- */
-
-import { type ExecuteToolRequest, executeTool } from '@/lib/executor';
-import { type NextRequest, NextResponse } from 'next/server';
-
-export const runtime = 'nodejs';
-export const dynamic = 'force-dynamic';
-export const maxDuration = 60; // 60 seconds max
-
-/**
- * Verify API key if configured
- */
-function verifyApiKey(request: NextRequest): boolean {
-  const apiKey = process.env.EXECUTOR_API_KEY;
-
-  // If no API key is configured, allow all requests
-  if (!apiKey) {
-    return true;
-  }
-
-  const authHeader = request.headers.get('Authorization');
-  if (!authHeader) {
-    return false;
-  }
-
-  // Expect "Bearer <api-key>" format
-  const [type, token] = authHeader.split(' ');
-  if (type !== 'Bearer' || token !== apiKey) {
-    return false;
-  }
-
-  return true;
-}
-
-/**
- * Validate the request body
- */
-function validateRequest(body: unknown): body is ExecuteToolRequest {
-  if (!body || typeof body !== 'object') {
-    return false;
-  }
-
-  const req = body as Record<string, unknown>;
-
-  return (
-    typeof req.packageName === 'string' &&
-    req.packageName.length > 0 &&
-    typeof req.name === 'string' &&
-    req.name.length > 0 &&
-    typeof req.params === 'object' &&
-    req.params !== null
-  );
-}
-
-export async function POST(request: NextRequest): Promise<NextResponse> {
-  // Verify API key if configured
-  if (!verifyApiKey(request)) {
-    return NextResponse.json(
-      { success: false, error: 'Unauthorized', executionTimeMs: 0 },
-      { status: 401 }
-    );
-  }
-
-  try {
-    const body = await request.json();
-
-    // Validate request
-    if (!validateRequest(body)) {
-      return NextResponse.json(
-        {
-          success: false,
-          error: 'Invalid request. Required: packageName, name, params',
-          executionTimeMs: 0,
-        },
-        { status: 400 }
-      );
-    }
-
-    // Execute the tool
-    const result = await executeTool(body);
-
-    return NextResponse.json(result, {
-      status: result.success ? 200 : 500,
-    });
-  } catch (error) {
-    return NextResponse.json(
-      {
-        success: false,
-        error: error instanceof Error ? error.message : 'Internal server error',
-        executionTimeMs: 0,
-      },
-      { status: 500 }
-    );
-  }
-}
-
-// Handle OPTIONS for CORS preflight
-export async function OPTIONS(): Promise<NextResponse> {
-  return new NextResponse(null, {
-    status: 200,
-    headers: {
-      'Access-Control-Allow-Origin': '*',
-      'Access-Control-Allow-Methods': 'POST, OPTIONS',
-      'Access-Control-Allow-Headers': 'Content-Type, Authorization',
-    },
-  });
-}

templates/vercel-executor/app/api/health/route.ts

@@ -1,40 +0,0 @@
-/**
- * Health Check Endpoint
- *
- * GET /api/health
- * Returns the health status of the executor
- */
-
-import { NextResponse } from 'next/server';
-
-export const runtime = 'nodejs';
-export const dynamic = 'force-dynamic';
-
-interface HealthResponse {
-  status: 'ok' | 'degraded' | 'error';
-  version?: string;
-  info?: Record<string, unknown>;
-}
-
-export async function GET(): Promise<NextResponse<HealthResponse>> {
-  return NextResponse.json({
-    status: 'ok',
-    version: '1.0.0',
-    info: {
-      runtime: 'vercel-serverless',
-      timestamp: new Date().toISOString(),
-    },
-  });
-}
-
-// Handle OPTIONS for CORS preflight
-export async function OPTIONS(): Promise<NextResponse> {
-  return new NextResponse(null, {
-    status: 200,
-    headers: {
-      'Access-Control-Allow-Origin': '*',
-      'Access-Control-Allow-Methods': 'GET, OPTIONS',
-      'Access-Control-Allow-Headers': 'Content-Type, Authorization',
-    },
-  });
-}

templates/vercel-executor/app/layout.tsx

@@ -1,11 +0,0 @@
-export default function RootLayout({
-  children,
-}: {
-  children: React.ReactNode;
-}) {
-  return (
-    <html lang="en">
-      <body>{children}</body>
-    </html>
-  );
-}

templates/vercel-executor/app/page.tsx

@@ -1,20 +0,0 @@
-export default function Home() {
-  return (
-    <div style={{ padding: '2rem', fontFamily: 'system-ui, sans-serif' }}>
-      <h1>TPMJS Executor</h1>
-      <p>This is a TPMJS tool executor service.</p>
-      <h2>Endpoints</h2>
-      <ul>
-        <li>
-          <code>GET /api/health</code> - Health check
-        </li>
-        <li>
-          <code>POST /api/execute-tool</code> - Execute a tool
-        </li>
-      </ul>
-      <p>
-        <a href="https://tpmjs.com/docs/executors">Documentation</a>
-      </p>
-    </div>
-  );
-}