fix: resolve Next.js routing and package-executor build errors

**API Route Restructuring:**
- Move execute endpoint from /api/tools/[...slug]/execute to /api/tools/execute/[...slug]
- Move simulations endpoint from /api/tools/[...slug]/simulations to /api/tools/simulations/[...slug]
- Fix Next.js App Router constraint: catch-all segments must be terminal
- Update ToolPlayground component to use new endpoint paths

**Package Executor Export Fix:**
- Remove .js extensions from exports in @tpmjs/package-executor
- Change from './types.js' to './types' for proper TypeScript resolution
- Change from './executor.js' to './executor' for proper TypeScript resolution
- Fixes "Export executePackage doesn't exist in target module" build error

**Next.js Configuration:**
- Add vm2 and @tpmjs/package-executor to serverExternalPackages
- Prevents bundling VM2 which requires filesystem access to internal files

**Code Quality:**
- Add biome-ignore for excessive complexity in SSE stream handling
- Add biome-ignore for decorative loading spinner SVGs (2 instances)

Note: VM2 sandboxing still has compatibility issues with Next.js Turbopack.
This may need to be replaced with a different sandboxing approach or disabled.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

apps/web/next.config.ts

@@ -3,6 +3,7 @@ import type { NextConfig } from 'next';
 const nextConfig: NextConfig = {
   transpilePackages: ['@tpmjs/ui', '@tpmjs/utils', '@tpmjs/db', '@tpmjs/types', '@tpmjs/env'],
   reactStrictMode: true,
+  serverExternalPackages: ['vm2', '@tpmjs/package-executor'],
 };
 
 export default nextConfig;

apps/web/src/components/ToolPlayground.tsx

@@ -32,6 +32,7 @@ export function ToolPlayground({ tool }: ToolPlaygroundProps): React.ReactElemen
   const [error, setError] = useState<string | null>(null);
   const [rateLimitInfo, setRateLimitInfo] = useState<{ remaining: number } | null>(null);
 
+  // biome-ignore lint/complexity/noExcessiveCognitiveComplexity: SSE stream handling requires sequential logic
   const handleExecute = async () => {
     if (!prompt.trim() || isExecuting) return;
 
@@ -44,7 +45,7 @@ export function ToolPlayground({ tool }: ToolPlaygroundProps): React.ReactElemen
 
     try {
       const response = await fetch(
-        `/api/tools/${encodeURIComponent(tool.npmPackageName)}/execute`,
+        `/api/tools/execute/${encodeURIComponent(tool.npmPackageName)}`,
         {
           method: 'POST',
           headers: {
@@ -253,6 +254,7 @@ export function ToolPlayground({ tool }: ToolPlaygroundProps): React.ReactElemen
             >
               {isExecuting ? (
                 <span className="flex items-center">
+                  {/* biome-ignore lint/a11y/noSvgWithoutTitle: decorative loading spinner */}
                   <svg
                     className="animate-spin -ml-1 mr-3 h-5 w-5"
                     xmlns="http://www.w3.org/2000/svg"
@@ -298,6 +300,7 @@ export function ToolPlayground({ tool }: ToolPlaygroundProps): React.ReactElemen
             ) : isExecuting ? (
               <div className="flex items-center justify-center py-12">
                 <div className="text-center">
+                  {/* biome-ignore lint/a11y/noSvgWithoutTitle: decorative loading spinner */}
                   <svg
                     className="animate-spin h-8 w-8 text-primary mx-auto mb-4"
                     xmlns="http://www.w3.org/2000/svg"

packages/package-executor/src/index.ts

@@ -3,5 +3,5 @@
  * @packageDocumentation
  */
 
-export * from './types.js';
-export * from './executor.js';
+export * from './types';
+export * from './executor';