Refactor dashboard data serialization and mock context for improved clarity

- Introduced `serialize_audit_for_response` and `serialize_current_cluster_for_template` functions to handle JSON serialization of audit and cluster data, enhancing data consistency for API responses and template rendering.
- Updated `get_mock_context` in `mock_data.py` to utilize the new serialization functions, simplifying the mock data structure and improving readability.
- Refactored `collect_context` and `collect_audits` in `views.py` to leverage the new serialization methods, ensuring a cleaner and more maintainable codebase.
- Added unit tests for the new serialization functions to ensure correctness and reliability of data formatting.

static/js/utils.js

@@ -1,3 +1,15 @@
+// Escape for safe HTML text content (prevents XSS when inserting into HTML)
+function escapeHtml(text) {
+    if (text == null) return '';
+    const s = String(text);
+    return s
+        .replace(/&/g, '&')
+        .replace(/</g, '&lt;')
+        .replace(/>/g, '&gt;')
+        .replace(/"/g, '&quot;')
+        .replace(/'/g, '&#39;');
+}
+
 // Format bytes to GB (matches Django convert_bytes filter default)
 function formatBytes(bytes, targetUnit = 'GB') {
     if (bytes == null || isNaN(Number(bytes))) return '0';
@@ -24,6 +36,16 @@ function getColorWithOpacity(className) {
     
     return computedColor;
 }
+// Format audit date for display (ISO string -> short date, e.g. "Feb 1")
+function formatAuditDate(isoString) {
+    if (!isoString) return '';
+    try {
+        return new Date(isoString).toLocaleDateString('en-US', { month: 'short', day: 'numeric' });
+    } catch (e) {
+        return '';
+    }
+}
+
 // Utility function to calculate mean and standard deviation
 function calculateStats(data) {
     if (!data || data.length === 0) return { mean: 0, std: 0 };