fix: Docker build and runtime fixes

- Fix duplicate 'signature' variable in webhooks.ts
- Add Prisma binary target for Alpine Linux
- Fix tsconfig path alias (@/* -> ./src/*)
- Add missing next-themes dependency
- Add build args for NEXT_PUBLIC_* env vars
- Fix SSR issues with zustand and providers
- Add providers-wrapper with dynamic ssr:false import
- Add SSL certs and public dir for nginx
- Update Dockerfiles for proper Prisma engine handling

frontend/src/components/providers-wrapper.tsx

@@ -0,0 +1,13 @@
+'use client';
+
+import dynamic from 'next/dynamic';
+import { ReactNode } from 'react';
+
+const DynamicProviders = dynamic(
+  () => import('./providers').then((mod) => ({ default: mod.Providers })),
+  { ssr: false }
+);
+
+export function ProvidersWrapper({ children }: { children: ReactNode }) {
+  return <DynamicProviders>{children}</DynamicProviders>;
+}