feat: Comment edit/delete, auto-link URLs, markdown tables, mobile fixes

- Add comment edit/delete functionality (owner or admin can modify)
- Add edit/delete buttons to comments in TicketView
- Create update_comment.php and delete_comment.php API endpoints
- Add updateComment() and deleteComment() methods to CommentModel
- Show "(edited)" indicator on modified comments
- Add migration script for updated_at column

- Auto-link URLs in plain text comments (non-markdown)
- Add markdown table support with proper HTML rendering
- Preserve code blocks during markdown parsing

- Fix mobile UI elements showing on desktop (add display:none defaults)
- Add mobile styles for CreateTicketView form elements
- Stack status-priority-row on mobile devices

- Update cache busters to v20260124e
- Update Claude.md and README.md documentation

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

models/CommentModel.php

@@ -115,5 +115,87 @@ class CommentModel {
             ];
         }
     }
+
+    /**
+     * Get a single comment by ID
+     */
+    public function getCommentById($commentId) {
+        $sql = "SELECT tc.*, u.display_name, u.username
+                FROM ticket_comments tc
+                LEFT JOIN users u ON tc.user_id = u.user_id
+                WHERE tc.comment_id = ?";
+        $stmt = $this->conn->prepare($sql);
+        $stmt->bind_param("i", $commentId);
+        $stmt->execute();
+        $result = $stmt->get_result();
+        return $result->fetch_assoc();
+    }
+
+    /**
+     * Update an existing comment
+     * Only the comment owner or an admin can update
+     */
+    public function updateComment($commentId, $commentText, $markdownEnabled, $userId, $isAdmin = false) {
+        // First check if user owns this comment or is admin
+        $comment = $this->getCommentById($commentId);
+
+        if (!$comment) {
+            return ['success' => false, 'error' => 'Comment not found'];
+        }
+
+        if ($comment['user_id'] != $userId && !$isAdmin) {
+            return ['success' => false, 'error' => 'You do not have permission to edit this comment'];
+        }
+
+        $sql = "UPDATE ticket_comments SET comment_text = ?, markdown_enabled = ?, updated_at = NOW() WHERE comment_id = ?";
+        $stmt = $this->conn->prepare($sql);
+        $markdownInt = $markdownEnabled ? 1 : 0;
+        $stmt->bind_param("sii", $commentText, $markdownInt, $commentId);
+
+        if ($stmt->execute()) {
+            return [
+                'success' => true,
+                'comment_id' => $commentId,
+                'comment_text' => $commentText,
+                'markdown_enabled' => $markdownInt,
+                'updated_at' => date('M d, Y H:i')
+            ];
+        } else {
+            return ['success' => false, 'error' => $this->conn->error];
+        }
+    }
+
+    /**
+     * Delete a comment
+     * Only the comment owner or an admin can delete
+     */
+    public function deleteComment($commentId, $userId, $isAdmin = false) {
+        // First check if user owns this comment or is admin
+        $comment = $this->getCommentById($commentId);
+
+        if (!$comment) {
+            return ['success' => false, 'error' => 'Comment not found'];
+        }
+
+        if ($comment['user_id'] != $userId && !$isAdmin) {
+            return ['success' => false, 'error' => 'You do not have permission to delete this comment'];
+        }
+
+        $ticketId = $comment['ticket_id'];
+
+        $sql = "DELETE FROM ticket_comments WHERE comment_id = ?";
+        $stmt = $this->conn->prepare($sql);
+        $stmt->bind_param("i", $commentId);
+
+        if ($stmt->execute()) {
+            return [
+                'success' => true,
+                'comment_id' => $commentId,
+                'ticket_id' => $ticketId
+            ];
+        } else {
+            return ['success' => false, 'error' => $this->conn->error];
+        }
+    }
 }
 ?>