fix: resolve __dirname error by forcing Node.js runtime on all server routes

- Add serverExternalPackages for @supabase/ssr in next.config.ts
- Add export const runtime = 'nodejs' to all pages/routes using Supabase
- Replace createAdminClient to use @supabase/supabase-js directly (no SSR)
- Prevents @supabase/ssr from running in Edge runtime on Vercel

https://claude.ai/code/session_01H2aRGDaKgarPvhay2HxN6Y

app/(protected)/dashboard/page.tsx

@@ -4,6 +4,8 @@ import ProgressBar from "@/components/dashboard/ProgressBar";
 import ModuleCard from "@/components/dashboard/ModuleCard";
 import type { Module, UserProgress, Profile } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 export default async function DashboardPage() {
   const supabase = await createClient();
 

app/(protected)/formations/[moduleId]/page.tsx

@@ -5,6 +5,8 @@ import Card from "@/components/ui/Card";
 import MarkCompleteButton from "./MarkCompleteButton";
 import type { Module, UserProgress } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 interface ModulePageProps {
   params: Promise<{ moduleId: string }>;
 }

app/(protected)/formations/page.tsx

@@ -3,6 +3,8 @@ import ModuleCard from "@/components/dashboard/ModuleCard";
 import ProgressBar from "@/components/dashboard/ProgressBar";
 import type { Module, UserProgress } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 export default async function FormationsPage() {
   const supabase = await createClient();
 

app/(protected)/layout.tsx

@@ -3,6 +3,8 @@ import { createClient } from "@/lib/supabase/server";
 import Sidebar from "@/components/dashboard/Sidebar";
 import type { Profile } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 export default async function DashboardLayout({
   children,
 }: {

app/api/candidature/route.ts

@@ -2,6 +2,8 @@ import { NextResponse } from "next/server";
 import { createAdminClient } from "@/lib/supabase/server";
 import type { CandidatureInsert } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 export async function POST(request: Request) {
   try {
     const body = await request.json();

app/api/formations/[moduleId]/route.ts

@@ -2,6 +2,8 @@ import { NextResponse } from "next/server";
 import { createClient } from "@/lib/supabase/server";
 import type { Module, UserProgress } from "@/types/database.types";
 
+export const runtime = "nodejs";
+
 // GET /api/formations/[moduleId] - Récupérer un module
 export async function GET(
   _request: Request,

app/api/stripe/create-checkout/route.ts

@@ -2,6 +2,8 @@ import { NextResponse } from "next/server";
 import { stripe } from "@/lib/stripe/client";
 import { getBaseUrl } from "@/lib/utils";
 
+export const runtime = "nodejs";
+
 export async function POST(request: Request) {
   try {
     const body = await request.json();