Fix bugs and add features to Znakopis document management

- Fix API endpoint for creating pages (documents/:id/pages)
- Fix sentence deletion functionality
- Add CreateDocumentDialog component for better UX
- Improve document and sentence management UI
- Update seed data and backend routes
- Clean up documentation files (remove videos.md, videosentence.md)
- Add comprehensive bug tracking in fixbugsaddfeatures.md

packages/backend/prisma/seed.ts

@@ -7,10 +7,12 @@ async function main() {
   console.log('🌱 Starting database seed...');
 
   // Create admin user
-  const adminPasswordHash = await bcrypt.hash('admin123', 10);
+  const adminPasswordHash = await bcrypt.hash('novinet01', 10);
   const admin = await prisma.user.upsert({
     where: { email: 'admin@znakovni.hr' },
-    update: {},
+    update: {
+      passwordHash: adminPasswordHash, // Update password if user exists
+    },
     create: {
       email: 'admin@znakovni.hr',
       displayName: 'Administrator',
@@ -23,7 +25,7 @@ async function main() {
 
   console.log('✅ Created admin user:', admin.email);
   console.log('   Email: admin@znakovni.hr');
-  console.log('   Password: admin123');
+  console.log('   Password: novinet01');
 
   // Create a demo regular user
   const demoPasswordHash = await bcrypt.hash('demo123', 10);