Add ticket types, move Asiakaspalvelu tab first, hide closed tickets

- Asiakaspalvelu tab moved to first position in navigation
- Added ticket type field (Laskutus, Tekniikka, Vika, Muu) with
  type filter dropdown and type column in ticket list
- Type selector in ticket detail view with API endpoint
- Closed tickets hidden by default (selectable via "Kaikki tilat")
- Käsittelyssä rows highlighted with green background
- Type badges with color coding per category

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

api.php

@@ -1655,6 +1655,40 @@ switch ($action) {
         saveTickets($tickets);
         break;
 
+    case 'ticket_type':
+        requireAuth();
+        if ($method !== 'POST') break;
+        $input = json_decode(file_get_contents('php://input'), true);
+        $id = $input['id'] ?? '';
+        $type = $input['type'] ?? '';
+        $validTypes = ['laskutus', 'tekniikka', 'vika', 'muu'];
+        if (!in_array($type, $validTypes)) {
+            http_response_code(400);
+            echo json_encode(['error' => 'Virheellinen tyyppi']);
+            break;
+        }
+        $tickets = loadTickets();
+        $found = false;
+        foreach ($tickets as &$t) {
+            if ($t['id'] === $id) {
+                $oldType = $t['type'] ?? 'muu';
+                $t['type'] = $type;
+                $t['updated'] = date('Y-m-d H:i:s');
+                $found = true;
+                addLog('ticket_type', $t['id'], $t['subject'], "Tyyppi: {$oldType} → {$type}");
+                echo json_encode($t);
+                break;
+            }
+        }
+        unset($t);
+        if (!$found) {
+            http_response_code(404);
+            echo json_encode(['error' => 'Tikettiä ei löydy']);
+            break;
+        }
+        saveTickets($tickets);
+        break;
+
     case 'ticket_assign':
         requireAuth();
         if ($method !== 'POST') break;