feat(audience-sdk): add EnableMobileAttribution + SKAdNetworkIds config (SDK-305)

src/Packages/Audience/Runtime/AudienceConfig.cs

@@ -49,6 +49,40 @@ public class AudienceConfig
         /// </summary>
         public bool Debug { get; set; } = false;
 
+        /// <summary>
+        /// Opts into mobile install-attribution signals (iOS ATT / IDFA /
+        /// SKAdNetwork, Android Advertising ID / Install Referrer). Default
+        /// <c>false</c>.
+        /// </summary>
+        /// <remarks>
+        /// Two gates control attribution; both must be set for any data to
+        /// ship:
+        ///
+        /// 1. Build-time: add <c>AUDIENCE_MOBILE_ATTRIBUTION</c> to Player
+        ///    Settings → Other Settings → Scripting Define Symbols. Controls
+        ///    the AD_ID Android manifest permission, the iOS Privacy Manifest
+        ///    variant (<c>NSPrivacyTracking</c>), and whether native
+        ///    attribution code is compiled into the binary.
+        ///
+        /// 2. Runtime: this flag. Controls whether attribution data is
+        ///    collected at runtime. Without the define, this setter is a
+        ///    no-op.
+        ///
+        /// Studios who set neither ship a clean binary — no AD_ID permission,
+        /// no native attribution code, <c>NSPrivacyTracking = false</c>.
+        /// </remarks>
+        public bool EnableMobileAttribution { get; set; } = false;
+
+        /// <summary>
+        /// SKAdNetwork IDs the iOS post-processor injects into <c>Info.plist</c>
+        /// at build time. Ignored on Android.
+        /// </summary>
+        /// <remarks>
+        /// Read only when <see cref="EnableMobileAttribution"/> and the
+        /// <c>AUDIENCE_MOBILE_ATTRIBUTION</c> scripting define are both set.
+        /// </remarks>
+        public string[]? SKAdNetworkIds { get; set; }
+
         /// <summary>
         /// Interval between automatic flushes to the backend, in seconds.
         /// </summary>

src/Packages/Audience/Tests/Runtime/AudienceConfigTests.cs

@@ -0,0 +1,41 @@
+#nullable enable
+
+using NUnit.Framework;
+
+namespace Immutable.Audience.Tests
+{
+    [TestFixture]
+    internal class AudienceConfigTests
+    {
+        [Test]
+        public void EnableMobileAttribution_DefaultsToFalse()
+        {
+            // Default-off matters: a studio that never opts in must ship a
+            // clean binary, no AD_ID permission, NSPrivacyTracking false.
+            var config = new AudienceConfig();
+            Assert.IsFalse(config.EnableMobileAttribution);
+        }
+
+        [Test]
+        public void SKAdNetworkIds_DefaultsToNull()
+        {
+            var config = new AudienceConfig();
+            Assert.IsNull(config.SKAdNetworkIds);
+        }
+
+        [Test]
+        public void EnableMobileAttribution_RoundTrips()
+        {
+            var config = new AudienceConfig { EnableMobileAttribution = true };
+            Assert.IsTrue(config.EnableMobileAttribution);
+        }
+
+        [Test]
+        public void SKAdNetworkIds_RoundTrips()
+        {
+            var ids = new[] { "abc123.skadnetwork", "def456.skadnetwork" };
+            var config = new AudienceConfig { SKAdNetworkIds = ids };
+            Assert.AreSame(ids, config.SKAdNetworkIds);
+        }
+    }
+}