Add SMS bulk delay configuration and validate coupon phone function

app/Jobs/SendSmsToCouponJob.php

@@ -0,0 +1,81 @@
+<?php
+
+namespace App\Jobs;
+
+use App\Enums\SmsSendStatus;
+use App\Models\Coupon;
+use App\Models\SmsCampaign;
+use App\Models\SmsSendLog;
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Illuminate\Foundation\Queue\Queueable;
+use Illuminate\Queue\SerializesModels;
+
+class SendSmsToCouponJob implements ShouldQueue
+{
+    use Queueable;
+    use SerializesModels;
+
+    public int $tries = 3;
+
+    public function __construct(
+        public SmsCampaign $campaign,
+        public Coupon $coupon,
+    ) {
+        $this->onQueue('sms');
+    }
+
+    public function handle(): void
+    {
+        $log = SmsSendLog::query()
+            ->where('sms_campaign_id', $this->campaign->id)
+            ->where('coupon_id', $this->coupon->id)
+            ->first();
+
+        if ($log === null) {
+            return;
+        }
+
+        if (! is_valid_coupon_phone($this->coupon->phone)) {
+            $this->markSkipped($log);
+
+            return;
+        }
+
+        $success = sendSMS($this->coupon->phone, $this->campaign->message);
+
+        $log->update([
+            'status' => $success ? SmsSendStatus::Sent : SmsSendStatus::Failed,
+            'error_message' => $success ? null : 'SMS API request failed',
+            'attempted_at' => now(),
+        ]);
+
+        $this->campaign->increment($success ? 'sent_count' : 'failed_count');
+        $this->markCampaignCompleteIfFinished();
+
+        usleep((int) config('services.sms.bulk_delay_ms', 300) * 1000);
+    }
+
+    protected function markSkipped(SmsSendLog $log): void
+    {
+        if ($log->status === SmsSendStatus::SkippedInvalid) {
+            return;
+        }
+
+        $log->update([
+            'status' => SmsSendStatus::SkippedInvalid,
+            'attempted_at' => now(),
+        ]);
+
+        $this->campaign->increment('skipped_count');
+        $this->markCampaignCompleteIfFinished();
+    }
+
+    protected function markCampaignCompleteIfFinished(): void
+    {
+        $this->campaign->refresh();
+
+        if ($this->campaign->processedCount() >= $this->campaign->recipient_count) {
+            $this->campaign->update(['completed_at' => now()]);
+        }
+    }
+}