feat(jobs): add cache-based deduplication for delayed cron execution

Implements getPreviousRunDate() + cache-based tracking in shouldRunNow()
to prevent duplicate dispatch of scheduled jobs when queue delays push
execution past the cron minute. This resilience ensures jobs catch missed
windows without double-dispatching within the same cron window.

Updated scheduled job dispatches to include dedupKey parameter:
- Docker cleanup operations
- Server connection checks
- Sentinel restart checks
- Server storage checks
- Server patch checks

DockerCleanupJob now dispatches on the 'high' queue for faster processing.

Includes comprehensive test coverage for dedup behavior across different
cron schedules and delay scenarios.

tests/Feature/ServerManagerJobShouldRunNowTest.php

@@ -0,0 +1,102 @@
+<?php
+
+use App\Jobs\ServerManagerJob;
+use Illuminate\Support\Carbon;
+use Illuminate\Support\Facades\Cache;
+
+beforeEach(function () {
+    Cache::flush();
+});
+
+it('catches delayed sentinel restart when job runs past midnight', function () {
+    // Simulate previous dispatch yesterday at midnight
+    Cache::put('sentinel-restart:1', Carbon::create(2026, 2, 27, 0, 0, 0, 'UTC')->toIso8601String(), 86400);
+
+    // Job runs 3 minutes late at 00:03
+    Carbon::setTestNow(Carbon::create(2026, 2, 28, 0, 3, 0, 'UTC'));
+
+    $job = new ServerManagerJob;
+    $reflection = new ReflectionClass($job);
+
+    $executionTimeProp = $reflection->getProperty('executionTime');
+    $executionTimeProp->setAccessible(true);
+    $executionTimeProp->setValue($job, Carbon::now());
+
+    $method = $reflection->getMethod('shouldRunNow');
+    $method->setAccessible(true);
+
+    // isDue() would return false at 00:03, but getPreviousRunDate() = 00:00 today
+    // lastDispatched = yesterday 00:00 → today 00:00 > yesterday → fires
+    $result = $method->invoke($job, '0 0 * * *', 'UTC', 'sentinel-restart:1');
+
+    expect($result)->toBeTrue();
+});
+
+it('catches delayed weekly patch check when job runs past the cron minute', function () {
+    // Simulate previous dispatch last Sunday at midnight
+    Cache::put('server-patch-check:1', Carbon::create(2026, 2, 22, 0, 0, 0, 'UTC')->toIso8601String(), 86400);
+
+    // This Sunday at 00:02 — job was delayed 2 minutes
+    // 2026-03-01 is a Sunday
+    Carbon::setTestNow(Carbon::create(2026, 3, 1, 0, 2, 0, 'UTC'));
+
+    $job = new ServerManagerJob;
+    $reflection = new ReflectionClass($job);
+
+    $executionTimeProp = $reflection->getProperty('executionTime');
+    $executionTimeProp->setAccessible(true);
+    $executionTimeProp->setValue($job, Carbon::now());
+
+    $method = $reflection->getMethod('shouldRunNow');
+    $method->setAccessible(true);
+
+    $result = $method->invoke($job, '0 0 * * 0', 'UTC', 'server-patch-check:1');
+
+    expect($result)->toBeTrue();
+});
+
+it('catches delayed storage check when job runs past the cron minute', function () {
+    // Simulate previous dispatch yesterday at 23:00
+    Cache::put('server-storage-check:5', Carbon::create(2026, 2, 27, 23, 0, 0, 'UTC')->toIso8601String(), 86400);
+
+    // Today at 23:04 — job was delayed 4 minutes
+    Carbon::setTestNow(Carbon::create(2026, 2, 28, 23, 4, 0, 'UTC'));
+
+    $job = new ServerManagerJob;
+    $reflection = new ReflectionClass($job);
+
+    $executionTimeProp = $reflection->getProperty('executionTime');
+    $executionTimeProp->setAccessible(true);
+    $executionTimeProp->setValue($job, Carbon::now());
+
+    $method = $reflection->getMethod('shouldRunNow');
+    $method->setAccessible(true);
+
+    $result = $method->invoke($job, '0 23 * * *', 'UTC', 'server-storage-check:5');
+
+    expect($result)->toBeTrue();
+});
+
+it('does not double-dispatch within same cron window', function () {
+    Carbon::setTestNow(Carbon::create(2026, 2, 28, 0, 0, 0, 'UTC'));
+
+    $job = new ServerManagerJob;
+    $reflection = new ReflectionClass($job);
+
+    $executionTimeProp = $reflection->getProperty('executionTime');
+    $executionTimeProp->setAccessible(true);
+    $executionTimeProp->setValue($job, Carbon::now());
+
+    $method = $reflection->getMethod('shouldRunNow');
+    $method->setAccessible(true);
+
+    $first = $method->invoke($job, '0 0 * * *', 'UTC', 'sentinel-restart:10');
+    expect($first)->toBeTrue();
+
+    // Next minute — should NOT dispatch again
+    Carbon::setTestNow(Carbon::create(2026, 2, 28, 0, 1, 0, 'UTC'));
+    $executionTimeProp->setValue($job, Carbon::now());
+
+    $second = $method->invoke($job, '0 0 * * *', 'UTC', 'sentinel-restart:10');
+    expect($second)->toBeFalse();
+});