refactor: sjednoceni zdroje casu na MySQL NOW() + audit log cleanup a UI

- attendance handlery pouzivaji getDbNow() misto PHP date()
- nova helper funkce getDbNow() v AttendanceHelpers.php
- audit log: cleanup endpoint (POST) s volbou stari zaznamu
- audit log: filtry na jednom radku
- dashboard: aktivita prejmenovana na Audit log s odkazem

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

api/admin/audit-log.php

@@ -26,12 +26,44 @@ if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
     exit;
 }
 
-if ($_SERVER['REQUEST_METHOD'] !== 'GET') {
+if (!in_array($_SERVER['REQUEST_METHOD'], ['GET', 'POST'], true)) {
     errorResponse('Method not allowed', 405);
 }
 
 requirePermission($authData, 'settings.audit');
 
+if ($_SERVER['REQUEST_METHOD'] === 'POST') {
+    $input = getJsonInput();
+    $action = $input['action'] ?? '';
+
+    if ($action !== 'cleanup') {
+        errorResponse('Neplatná akce');
+    }
+
+    $days = (int) ($input['days'] ?? 90);
+    $pdo = db();
+
+    if ($days === 0) {
+        $stmt = $pdo->query('DELETE FROM audit_logs');
+        $deleted = $stmt->rowCount();
+        $msg = $deleted > 0
+            ? "Smazáno všech $deleted záznamů"
+            : 'Audit log je prázdný';
+    } else {
+        $days = max(1, $days);
+        $stmt = $pdo->prepare(
+            'DELETE FROM audit_logs WHERE created_at < DATE_SUB(NOW(), INTERVAL ? DAY)'
+        );
+        $stmt->execute([$days]);
+        $deleted = $stmt->rowCount();
+        $msg = $deleted > 0
+            ? "Smazáno $deleted záznamů starších $days dní"
+            : "Žádné záznamy starší než $days dní nebyly nalezeny";
+    }
+
+    successResponse(['deleted' => $deleted], $msg);
+}
+
 $page = max(1, (int) ($_GET['page'] ?? 1));
 $perPage = max(1, min(100, (int) ($_GET['per_page'] ?? 50)));
 

api/admin/handlers/attendance-handlers.php

@@ -4,7 +4,8 @@ declare(strict_types=1);
 
 function handleGetCurrent(PDO $pdo, int $userId): void
 {
-    $today = date('Y-m-d');
+    $dbTime = getDbNow($pdo);
+    $today = $dbTime['today'];
 
     $stmt = $pdo->prepare("
         SELECT id, user_id, shift_date, arrival_time, arrival_lat, arrival_lng,
@@ -68,13 +69,13 @@ function handleGetCurrent(PDO $pdo, int $userId): void
 
     $leaveBalance = getLeaveBalance($pdo, $userId);
 
-    $currentYear = (int)date('Y');
-    $currentMonth = (int)date('m');
+    $currentYear = $dbTime['year'];
+    $currentMonth = $dbTime['month'];
     $fund = CzechHolidays::getMonthlyWorkFund($currentYear, $currentMonth);
     $businessDays = CzechHolidays::getBusinessDaysInMonth($currentYear, $currentMonth);
 
-    $startDate = date('Y-m-01');
-    $endDate = date('Y-m-t');
+    $startDate = substr($dbTime['today'], 0, 7) . '-01';
+    $endDate = date('Y-m-t', strtotime($startDate));
 
     $stmt = $pdo->prepare('
         SELECT id, user_id, shift_date, arrival_time, break_start, break_end,
@@ -253,8 +254,9 @@ function handlePunch(PDO $pdo, int $userId): void
 {
     $input = getJsonInput();
     $action = $input['punch_action'] ?? '';
-    $today = date('Y-m-d');
-    $rawNow = date('Y-m-d H:i:s');
+    $dbTime = getDbNow($pdo);
+    $today = $dbTime['today'];
+    $rawNow = $dbTime['now'];
 
     $lat = isset($input['latitude']) && $input['latitude'] !== '' ? (float)$input['latitude'] : null;
     $lng = isset($input['longitude']) && $input['longitude'] !== '' ? (float)$input['longitude'] : null;
@@ -508,7 +510,7 @@ function handleSwitchProject(PDO $pdo, int $userId): void
     }
 
     $attendanceId = $currentShift['id'];
-    $now = date('Y-m-d H:i:s');
+    $now = getDbNow($pdo)['now'];
 
     $stmt = $pdo->prepare(
         'UPDATE attendance_project_logs SET ended_at = ?

api/includes/AttendanceHelpers.php

@@ -6,6 +6,21 @@
 
 declare(strict_types=1);
 
+/**
+ * Vraci aktualni cas a datum z MySQL (jednotny zdroj casu)
+ * @return array{now: string, today: string, year: int, month: int}
+ */
+function getDbNow(PDO $pdo): array
+{
+    $row = $pdo->query("SELECT NOW() AS now, CURDATE() AS today, YEAR(NOW()) AS y, MONTH(NOW()) AS m")->fetch();
+    return [
+        'now' => $row['now'],
+        'today' => $row['today'],
+        'year' => (int)$row['y'],
+        'month' => (int)$row['m'],
+    ];
+}
+
 function roundUpTo15Minutes(string $datetime): string
 {
     $timestamp = strtotime($datetime);
@@ -327,15 +342,14 @@ function addFundDataToUserTotals(PDO $pdo, array &$userTotals, int $year, int $m
     }
     unset($ut);
 
-    $today = date('Y-m-d');
     $stmt = $pdo->prepare("
         SELECT DISTINCT user_id FROM attendance
-        WHERE shift_date = ?
+        WHERE shift_date = CURDATE()
         AND arrival_time IS NOT NULL
         AND departure_time IS NULL
         AND (leave_type IS NULL OR leave_type = 'work')
     ");
-    $stmt->execute([$today]);
+    $stmt->execute();
     $workingNow = $stmt->fetchAll(PDO::FETCH_COLUMN);
     foreach ($workingNow as $uid) {
         if (isset($userTotals[$uid])) {