fix: correct snake_case column names in session lookup SQL

Prisma maps sessionToken → session_token and userId → user_id
in the PostgreSQL sessions table. The forwardAuth query was using
the wrong camelCase column names.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/api/theia-auth/route.ts

@@ -48,8 +48,8 @@ export async function GET(request: NextRequest) {
     const result = await query<{ email: string; name: string }>(
       `SELECT u.email, u.name
          FROM sessions s
-         JOIN users u ON u.id = s."userId"
-        WHERE s."sessionToken" = $1
+         JOIN users u ON u.id = s.user_id
+        WHERE s.session_token = $1
           AND s.expires > NOW()
         LIMIT 1`,
       [sessionToken],