feat: Add notification services for Email, Telegram, and WhatsApp

- Implement EmailNotifier for sending batch and test notifications via email.
- Implement TelegramNotifier for sending batch and test notifications via Telegram.
- Implement WahaNotifier for sending batch and test notifications via WhatsApp using WAHA API.
- Create migration for client_categories table and update clients table to include category_id.
- Create migration for notification_settings table to manage notification configurations.
- Add ClientCategorySeeder to populate default client categories.
- Create manifest.json for PWA support.
- Implement service worker (sw.js) for caching static assets and offline support.
- Add edit event view for modifying scheduled events.
- Create search results view for displaying search queries.
- Develop notification settings view for configuring notification channels and triggers.

database/migrations/2024_01_01_000080_create_client_categories_table.php

@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('client_categories', function (Blueprint $table): void {
+            $table->id();
+            $table->string('name');
+            $table->string('slug')->unique();
+            $table->unsignedBigInteger('parent_id')->nullable();
+            $table->string('icon')->default('🏷️');
+            $table->string('color')->default('#FFB7C5');
+            $table->string('description')->nullable();
+            $table->boolean('is_system')->default(false);
+            $table->unsignedInteger('sort_order')->default(0);
+            $table->timestamps();
+
+            $table->foreign('parent_id')
+                  ->references('id')
+                  ->on('client_categories')
+                  ->onDelete('set null');
+        });
+
+        // Add category_id to clients table
+        Schema::table('clients', function (Blueprint $table): void {
+            $table->unsignedBigInteger('category_id')->nullable()->after('status');
+            $table->foreign('category_id')
+                  ->references('id')
+                  ->on('client_categories')
+                  ->onDelete('set null');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('clients', function (Blueprint $table): void {
+            $table->dropForeign(['category_id']);
+            $table->dropColumn('category_id');
+        });
+
+        Schema::dropIfExists('client_categories');
+    }
+};

database/migrations/2024_01_01_000090_create_notification_settings_table.php

@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('notification_settings', function (Blueprint $table): void {
+            $table->id();
+            $table->string('name');                      // e.g. "My Telegram Bot"
+            $table->string('channel');                   // email | telegram | whatsapp
+            $table->json('config');                      // channel-specific credentials
+            $table->json('triggers')->nullable();        // array: upcoming_event, invoice_due, content_due
+            $table->boolean('is_enabled')->default(true);
+            $table->integer('notify_before_hours')->default(24); // hours before event to notify
+            $table->timestamps();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('notification_settings');
+    }
+};