Fix PHP 8.2 TypeError crash in create_ticket_api.php on missing title

generateTicketHash() passed $data['title'] to preg_match() before any
input validation. In PHP 8.2, preg_match() with null subject throws
TypeError, causing HTTP 500 with empty body. hwmonDaemon saw this as
"Expecting value: line 1 column 1 (char 0)" and failed to create tickets
on all nodes.

Moved input validation before the hash call: missing or empty title now
returns HTTP 400 with proper JSON error instead of crashing. Also removed
the redundant late URL-encoded fallback.

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

create_ticket_api.php

@@ -84,6 +84,22 @@ $conn->query($createTableSQL);
 $rawInput = file_get_contents('php://input');
 $data = json_decode($rawInput, true);
 
+// Validate required fields before any processing
+if (!is_array($data) || empty($data['title'])) {
+    // Try URL-encoded fallback
+    if (empty($data['title'])) {
+        parse_str($rawInput, $urlData);
+        if (!empty($urlData['title'])) {
+            $data = $urlData;
+        }
+    }
+    if (!is_array($data) || empty($data['title'])) {
+        http_response_code(400);
+        echo json_encode(['success' => false, 'error' => 'title is required']);
+        exit;
+    }
+}
+
 // Generate hash from stable components
 function generateTicketHash($data) {
     // Extract device name if present (matches /dev/sdX, /dev/nvmeXnY patterns)
@@ -167,11 +183,6 @@ if ($result->num_rows > 0) {
 // Force JSON content type for all incoming requests
 header('Content-Type: application/json');
 
-if (!$data) {
-    // Try parsing as URL-encoded data
-    parse_str($rawInput, $data);
-}
-
 // Generate ticket ID (9-digit format with leading zeros)
 $ticket_id = sprintf('%09d', mt_rand(1, 999999999));