Update 13 files

- /TeacherDashboard/index.html
- /TeacherDashboard/TeacherDashboard.code-workspace
- /TeacherDashboard/components/resourceModal.html
- /TeacherDashboard/components/subjectModal.html
- /TeacherDashboard/components/topicModal.html
- /TeacherDashboard/js/main.js
- /TeacherDashboard/js/subjects/colors.js
- /TeacherDashboard/js/subjects/subjectManager.js
- /TeacherDashboard/js/subjects/SubjectModel.js
- /TeacherDashboard/js/subjects/SubjectStorage.js
- /TeacherDashboard/js/topics/TopicModel.js
- /TeacherDashboard/js/topics/topicManager.js
- /TeacherDashboard/styles/main.css

TeacherDashboard/js/subjects/SubjectModel.js

@@ -0,0 +1,47 @@
+export class SubjectModel {
+    constructor(data) {
+        this.id = data.id || crypto.randomUUID();
+        this.name = data.name;
+        this.description = data.description || '';
+        this.color = data.color;
+        this.icon = data.icon;
+        this.createdAt = data.createdAt || new Date().toISOString();
+        this.updatedAt = new Date().toISOString();
+        this.topics = data.topics || [];
+        this.resources = data.resources || [];
+        this.metadata = {
+            lastAccessed: new Date().toISOString(),
+            topicCount: 0,
+            resourceCount: 0
+        };
+        this.content = data.content || '';
+        this.materials = data.materials || [];
+    }
+
+    validate() {
+        const required = ['name', 'color', 'icon'];
+        const missing = required.filter(field => !this[field]);
+        
+        if (missing.length > 0) {
+            throw new Error(`Missing required fields: ${missing.join(', ')}`);
+        }
+        return true;
+    }
+
+    toJSON() {
+        return {
+            id: this.id,
+            name: this.name,
+            description: this.description,
+            color: this.color,
+            icon: this.icon,
+            createdAt: this.createdAt,
+            updatedAt: this.updatedAt,
+            topics: this.topics,
+            resources: this.resources,
+            metadata: this.metadata,
+            content: this.content,
+            materials: this.materials
+        };
+    }
+}