Fix type safety and TDS class naming issues

- bulk_operation.php: replace is_numeric() with strict int cast+equality to reject scientific notation
- AttachmentModel.php: fix bind_param type strings (s→i for integer ticket IDs)
- CommentModel.php: use strict !== comparison with (int) cast for user_id ownership checks
- ticket.js: replace all non-TDS class names (text-amber→lt-text-amber, btn→lt-btn variants, etc.)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

models/AttachmentModel.php

@@ -21,7 +21,7 @@ class AttachmentModel {
                 ORDER BY a.uploaded_at DESC";
 
         $stmt = $this->conn->prepare($sql);
-        $stmt->bind_param("s", $ticketId);
+        $stmt->bind_param("i", $ticketId);
         $stmt->execute();
         $result = $stmt->get_result();
 
@@ -61,7 +61,7 @@ class AttachmentModel {
                 VALUES (?, ?, ?, ?, ?, ?)";
 
         $stmt = $this->conn->prepare($sql);
-        $stmt->bind_param("sssisi", $ticketId, $filename, $originalFilename, $fileSize, $mimeType, $uploadedBy);
+        $stmt->bind_param("issisi", $ticketId, $filename, $originalFilename, $fileSize, $mimeType, $uploadedBy);
         $result = $stmt->execute();
 
         if ($result) {
@@ -97,7 +97,7 @@ class AttachmentModel {
                 WHERE ticket_id = ?";
 
         $stmt = $this->conn->prepare($sql);
-        $stmt->bind_param("s", $ticketId);
+        $stmt->bind_param("i", $ticketId);
         $stmt->execute();
         $result = $stmt->get_result();
         $row = $result->fetch_assoc();
@@ -113,7 +113,7 @@ class AttachmentModel {
         $sql = "SELECT COUNT(*) as count FROM ticket_attachments WHERE ticket_id = ?";
 
         $stmt = $this->conn->prepare($sql);
-        $stmt->bind_param("s", $ticketId);
+        $stmt->bind_param("i", $ticketId);
         $stmt->execute();
         $result = $stmt->get_result();
         $row = $result->fetch_assoc();

models/CommentModel.php

@@ -240,7 +240,7 @@ class CommentModel {
             return ['success' => false, 'error' => 'Comment not found'];
         }
 
-        if ($comment['user_id'] != $userId && !$isAdmin) {
+        if ($comment['user_id'] !== (int)$userId && !$isAdmin) {
             return ['success' => false, 'error' => 'You do not have permission to edit this comment'];
         }
 
@@ -286,7 +286,7 @@ class CommentModel {
             return ['success' => false, 'error' => 'Comment not found'];
         }
 
-        if ($comment['user_id'] != $userId && !$isAdmin) {
+        if ($comment['user_id'] !== (int)$userId && !$isAdmin) {
             return ['success' => false, 'error' => 'You do not have permission to delete this comment'];
         }