feat: Add comprehensive system enhancements

- Add version display above storage consumption in admin sidebar
- Fix storage consumption to stick to bottom of window using flexbox
- Add user upload settings to events (allow uploads, category selection)
- Enhance disk space tab to comprehensive system status view
- Add localized date formatting for German/English language support
- Remove quick actions from dashboard for cleaner interface
- Create user photo upload functionality for galleries
- Add database migration for user upload settings
- Update all TypeScript types and interfaces

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

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

backend/migrations/011_add_user_upload_settings.js

@@ -0,0 +1,23 @@
+exports.up = async function(knex) {
+  // Add user upload settings to events table
+  await knex.schema.alterTable('events', function(table) {
+    table.boolean('allow_user_uploads').defaultTo(false);
+    table.integer('upload_category_id').references('id').inTable('photo_categories').onDelete('SET NULL');
+  });
+  
+  // Add uploaded_by field to photos table to track who uploaded
+  await knex.schema.alterTable('photos', function(table) {
+    table.string('uploaded_by').defaultTo('admin'); // 'admin' or guest identifier
+  });
+};
+
+exports.down = async function(knex) {
+  await knex.schema.alterTable('events', function(table) {
+    table.dropColumn('allow_user_uploads');
+    table.dropColumn('upload_category_id');
+  });
+  
+  await knex.schema.alterTable('photos', function(table) {
+    table.dropColumn('uploaded_by');
+  });
+};