refactor: fix all 105 PHPStan 2 strict type findings across core and modules

Resolve all non-false-positive PHPStan 2 findings, reducing the baseline
from 486 to 382 entries (only unused-public false positives remain).

Categories fixed:
- Remove 39 redundant type checks (is_string, is_array, is_object, method_exists)
- Remove 12 no-op array_values() on already-sequential lists
- Simplify 13 null-coalesce on guaranteed offsets
- Remove 8 always-true instanceof checks
- Replace 12 redundant test assertions (assertTrue(true) → addToAssertionCount)
- Simplify 6 unnecessary nullsafe operators (?-> → ->)
- Fix 6 always-true !== '' comparisons
- Fix remaining: unset.offset, return.unusedType, staticMethod narrowing

53 files changed across core/, modules/, pages/, and tests/.

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

modules/helpdesk/lib/Module/Helpdesk/Service/BcODataGateway.php

@@ -141,9 +141,7 @@ class BcODataGateway
                 . '&$count=true'
                 . '&$orderby=' . rawurlencode($sortField . ' ' . $sortDir)
                 . $select;
-            if ($clauses !== []) {
-                $url .= '&$filter=' . rawurlencode(implode(' and ', $clauses));
-            }
+            $url .= '&$filter=' . rawurlencode(implode(' and ', $clauses));
 
             try {
                 $response = $this->request('GET', $url);
@@ -469,9 +467,6 @@ class BcODataGateway
         $rows = $this->extractODataValues($response);
         $mapped = [];
         foreach ($rows as $row) {
-            if (!is_array($row)) {
-                continue;
-            }
             $ticketNo = trim((string) ($row['No'] ?? ''));
             if ($ticketNo === '') {
                 continue;
@@ -1271,9 +1266,6 @@ class BcODataGateway
     {
         $uniqueRows = [];
         foreach ($rows as $row) {
-            if (!is_array($row)) {
-                continue;
-            }
 
             $no = trim((string) ($row['No'] ?? ''));
             $rowKey = $no !== '' ? $no : md5((string) json_encode($row));

modules/helpdesk/lib/Module/Helpdesk/Service/DebitorDetailService.php

@@ -645,7 +645,7 @@ class DebitorDetailService
 
             $billToNo = trim((string) ($contract['Bill_to_Cust_No'] ?? ''));
             $sellToNo = trim((string) ($contract['Sell_to_Cust_No'] ?? ''));
-            if ($customerNo !== '' && $billToNo !== $customerNo && $sellToNo !== $customerNo) {
+            if ($billToNo !== $customerNo && $sellToNo !== $customerNo) {
                 continue;
             }
 
@@ -1178,7 +1178,7 @@ class DebitorDetailService
         $days = isset($matches[1]) && $matches[1] !== '' ? (int) $matches[1] : 0;
         $hours = isset($matches[2]) && $matches[2] !== '' ? (int) $matches[2] : 0;
         $minutes = isset($matches[3]) && $matches[3] !== '' ? (int) $matches[3] : 0;
-        $secondsFloat = isset($matches[4]) && $matches[4] !== '' ? (float) $matches[4] : 0.0;
+        $secondsFloat = isset($matches[4]) ? (float) $matches[4] : 0.0;
         $seconds = (int) floor($secondsFloat);
 
         return ($days * 86400) + ($hours * 3600) + ($minutes * 60) + $seconds;

modules/helpdesk/lib/Module/Helpdesk/Service/RiskRadarService.php

@@ -332,7 +332,7 @@ final class RiskRadarService
         $days = isset($m[1]) && $m[1] !== '' ? (int) $m[1] : 0;
         $hours = isset($m[2]) && $m[2] !== '' ? (int) $m[2] : 0;
         $minutes = isset($m[3]) && $m[3] !== '' ? (int) $m[3] : 0;
-        $seconds = isset($m[4]) && $m[4] !== '' ? (int) floor((float) $m[4]) : 0;
+        $seconds = isset($m[4]) ? (int) floor((float) $m[4]) : 0;
 
         return ($days * 86400) + ($hours * 3600) + ($minutes * 60) + $seconds;
     }
@@ -355,7 +355,7 @@ final class RiskRadarService
     private static function resolveActivityTimestamp(array $ticket): ?int
     {
         $lastActivity = trim((string) ($ticket['Last_Activity_Date'] ?? ''));
-        if ($lastActivity !== '' && !str_starts_with($lastActivity, '0001-01-01')) {
+        if (!str_starts_with($lastActivity, '0001-01-01')) {
             $ts = strtotime($lastActivity);
             if (is_int($ts)) {
                 return $ts;

modules/helpdesk/lib/Module/Helpdesk/Service/SystemRecommendationEngine.php

@@ -244,7 +244,7 @@ class SystemRecommendationEngine
         return [
             'recommendations' => array_slice($deduped, 0, $maxItems),
             'meta' => [
-                'applied_rules' => array_values(array_keys($appliedRulesMap)),
+                'applied_rules' => array_keys($appliedRulesMap),
                 'max_items' => $maxItems,
                 'escalation_data_available' => $escalationAvailable,
             ],
@@ -379,9 +379,6 @@ class SystemRecommendationEngine
         $openTickets = [];
 
         foreach ($tickets as $ticket) {
-            if (!is_array($ticket)) {
-                continue;
-            }
 
             $state = trim((string) ($ticket['Ticket_State'] ?? ''));
             if (in_array($state, self::CLOSED_TICKET_STATES, true)) {

modules/helpdesk/lib/Module/Helpdesk/Service/TicketCommunicationService.php

@@ -193,9 +193,6 @@ class TicketCommunicationService
         // Collect support user name → ticket code mappings
         $supportUserNamesByTicket = [];
         foreach ($tickets as $ticket) {
-            if (!is_array($ticket)) {
-                continue;
-            }
             $no = trim((string) ($ticket['No'] ?? ''));
             $name = trim((string) ($ticket['Support_User_Name'] ?? ''));
             if ($no !== '' && $name !== '') {
@@ -784,7 +781,7 @@ class TicketCommunicationService
         }
 
         if (preg_match('/^(\d{2}:\d{2})(:\d{2})?/', $time, $m) === 1) {
-            return isset($m[2]) && $m[2] !== '' ? ($m[1] . $m[2]) : ($m[1] . ':00');
+            return isset($m[2]) ? ($m[1] . $m[2]) : ($m[1] . ':00');
         }
 
         return $time;
@@ -902,9 +899,6 @@ class TicketCommunicationService
 
         $nameMap = [];
         foreach ($contacts as $contact) {
-            if (!is_array($contact)) {
-                continue;
-            }
             $contactNo = strtoupper(trim((string) ($contact['No'] ?? '')));
             $contactName = trim((string) ($contact['Name'] ?? ''));
             if ($contactNo === '' || $contactName === '') {
@@ -1075,7 +1069,7 @@ class TicketCommunicationService
             }
         }
 
-        return $trimmed !== '' ? $trimmed : '';
+        return $trimmed;
     }
 
     private function normalizeActorRole(string $createdByType, string $actor): string