feat: completar fases 3 y 4 del roadmap mvp (gradebook, drag-and-drop, impersonacion) y actualizar README

frontend/views/classrooms/edit.html

@@ -3,9 +3,9 @@
 {% block title %}Edit Classroom - {{ classroom.code_display }}{% endblock %}
 
 {% block content %}
-<div class="container-fluid pt-5 mt-4">
+<div class="container-fluid px-0">
     <!-- Header -->
-    <div class="row mb-4 align-items-center">
+    <div class="row mb-3 align-items-center">
         <div class="col-md-7">
             <nav aria-label="breadcrumb">
                 <ol class="breadcrumb mb-1 small">
@@ -165,9 +165,13 @@
 {% endblock %}
 
 {% block extra_js %}
+<script type="application/json" id="buildingFloorsData">
+{{ building_floors|tojson|safe }}
+</script>
 <script>
 document.addEventListener('DOMContentLoaded', function() {
-    var buildingFloors = {{ building_floors|tojson }};
+    var buildingFloorsDataEl = document.getElementById('buildingFloorsData');
+    var buildingFloors = buildingFloorsDataEl ? JSON.parse(buildingFloorsDataEl.textContent || '{}') : {};
     
     var buildingSelect = document.getElementById('building_id');
     var newBuildingContainer = document.getElementById('newBuildingContainer');