Feature 3: Implement Status Transitions with Workflow Validation

Add comprehensive workflow management system for ticket status transitions:

- Created WorkflowModel.php for managing status transition rules
- Updated TicketController.php to load allowed transitions for each ticket
- Modified TicketView.php to display dynamic status dropdown with only allowed transitions
- Enhanced api/update_ticket.php with server-side workflow validation
- Added updateTicketStatus() JavaScript function for client-side status changes
- Included CSS styling for status select dropdown with color-coded states
- Transitions can require comments or admin privileges
- Status changes are validated against status_transitions table

This feature enforces proper ticket workflows and prevents invalid status changes.

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

assets/css/ticket.css

@@ -515,4 +515,59 @@ body.dark-mode .timeline-content {
     --border-color: #444;
     --text-muted: #a0aec0;
     --text-secondary: #cbd5e0;
-}
+}
+/* Status select dropdown */
+.status-select {
+    padding: 8px 16px;
+    border-radius: 6px;
+    font-weight: 500;
+    text-transform: uppercase;
+    font-size: 0.9em;
+    letter-spacing: 0.5px;
+    border: 2px solid transparent;
+    cursor: pointer;
+    transition: all 0.2s ease;
+}
+
+.status-select:hover {
+    opacity: 0.9;
+    border-color: rgba(255, 255, 255, 0.3);
+}
+
+.status-select:focus {
+    outline: none;
+    border-color: rgba(255, 255, 255, 0.5);
+}
+
+/* Status colors for dropdown */
+.status-select.status-open {
+    background-color: var(--status-open) !important;
+    color: white !important;
+}
+
+.status-select.status-in-progress {
+    background-color: var(--status-in-progress) !important;
+    color: #212529 !important;
+}
+
+.status-select.status-closed {
+    background-color: var(--status-closed) !important;
+    color: white !important;
+}
+
+.status-select.status-resolved {
+    background-color: #28a745 !important;
+    color: white !important;
+}
+
+/* Dropdown options inherit colors */
+.status-select option {
+    background-color: var(--bg-primary);
+    color: var(--text-primary);
+    padding: 8px;
+}
+
+body.dark-mode .status-select option {
+    background-color: #2d3748;
+    color: #f7fafc;
+}