feat: implement core notification functionality for iOS and Android - Add settings management, proper error handling, and platform-specific implementations

ios/Plugin/DailyNotificationConfig.swift

@@ -0,0 +1,31 @@
+/**
+ * DailyNotificationConfig.swift
+ * Daily Notification Plugin for Capacitor
+ *
+ * Provides configuration options for the notification plugin
+ */
+
+import Foundation
+
+/// Configuration options for the DailyNotification plugin
+///
+/// This singleton structure provides configurable options that can be modified
+/// to customize the plugin's behavior.
+public struct DailyNotificationConfig {
+    /// Shared instance for singleton access
+    public static var shared = DailyNotificationConfig()
+    
+    /// Maximum number of notifications that can be scheduled per day
+    public var maxNotificationsPerDay = 10
+    
+    /// Default timezone for notifications when none is specified
+    public var defaultTimeZone = TimeZone.current
+    
+    /// Whether debug logging is enabled
+    public var loggingEnabled = true
+    
+    /// Number of days to retain delivered notifications
+    public var retentionDays = 7
+    
+    private init() {}
+}