fix: [SDK-4523] Unity custom event nested property encoding

[fadi-george]

Description

One Line Summary

Fix Unity custom event properties losing nested objects/typed arrays on the way to the dashboard, plus add the GitHub Actions E2E workflow that runs the Appium suite against the demo app.

Details

Motivation

Linear: SDK-4523 Unity Custom Events.

OneSignal.User.TrackEvent(name, properties) on Unity was mangling complex property values on both Android and iOS. Given:

{
  "someNum": 123,
  "someFloat": 3.14159,
  "someObject": { "abc": "123", "nested": { "def": "456" }, "ghi": null },
  "someArray": [1, 2],
  "someMixedArray": [1, "2", { "abc": "123" }, null]
}

the dashboard received:

{
  "someArray": ["1", "2"],
  "someObject": [null, null, null],
  "someMixedArray": ["1", "2", null, ""]
}

Two root causes:

1. MiniJSON serializer (com.onesignal.unity.core/Runtime/Utilities/MiniJSON.cs) checked IList before IDictionary. Any dict-like type that also implements IList (Newtonsoft's JObject is the common case, since JContainer : IList<JToken>) was serialized as a JSON array of its child JProperty items, producing [null, null, null] for a 3-key object.
2. Android ToMap (com.onesignal.unity.android/Runtime/Utilities/AndroidJavaObjectExtensions.cs) switched on the concrete type Dictionary<string, object> only. JObject is not Dictionary<string, object>, so it fell into the IList case and was treated as a JSON array.

Demo on top of that used Newtonsoft.JsonConvert.DeserializeObject<Dictionary<string, object>>, which is exactly the path that surfaces JObject/JArray wrappers.

Scope

• Fixes nested object + nested array + typed-primitive (int, double) property encoding for OneSignal.User.TrackEvent on iOS and Android.
• Does not change the public Unity API. Direct callers using plain Dictionary<string, object> / List<object> continue to work as before.
• Adds the GitHub Actions E2E workflow that builds the Unity demo for Android emulator + iOS device and runs the shared Appium suite. Required for [SDK-4406] / future regression coverage of this fix.
• run-android.sh / run-ios.sh now auto-detect Unity (newest 6000.x under the Hub) and adb (ANDROID_HOME, ~/Library/Android/sdk, which adb, then Unity's bundled SDK) instead of hardcoding a specific editor version.

Changes by file

Area	File	Change
SDK	com.onesignal.unity.core/Runtime/Utilities/MiniJSON.cs	Check IDictionary before IList in SerializeValue
SDK	com.onesignal.unity.android/Runtime/Utilities/AndroidJavaObjectExtensions.cs	ToMap matches IDictionary before IList (replaces strict Dictionary<string, object>)
Demo	examples/demo/Assets/Scripts/UI/Dialogs/TrackEventDialog.cs	Parse JSON via SDK's MiniJSON (returns native Dictionary<string, object> / List<object>) instead of Newtonsoft, which returns JObject/JArray
Demo	examples/demo/run-android.sh, run-ios.sh	Auto-detect Unity + adb, with env-var overrides
CI	.github/workflows/e2e.yml, .github/actions/create-demo-env/action.yml, examples/demo/Assets/Scripts/Editor/BuildScript.cs	Add the Unity demo E2E workflow (Android emulator + iOS device) and demo .env action

Testing

Manual testing

• Sent TEST_JSON (see appium/tests/specs/10_event.spec.ts) on Android emulator (Pixel 6, API 34) and iOS Simulator (iPhone 16 Pro, iOS 26.2). Verified on the OneSignal dashboard that someObject is a nested object, someArray contains numbers (not strings), and someMixedArray preserves its inner object/null entries.
• Verified the existing tracked-event behavior (top-level scalars + nulls) still round-trips correctly.
• Ran ./run-android.sh and ./run-ios.sh with no UNITY_PATH / ADB set and confirmed they discover the newest installed Unity 6000.x and ~/Library/Android/sdk/platform-tools/adb.

Made temp changes to custom events section e.g.

            // ---- TEMP: SDK-4523 native nested-properties sanity check ----
            // Bypasses the dialog/MiniJSON parser to confirm Dictionary<string,object>
            // and List<object> nested data round-trips correctly to the dashboard.
            section.Add(
                SectionBuilder.CreatePrimaryButton(
                    "TRACK NATIVE TEST",
                    "track_native_test_button",
                    TrackNativeTest
                )
            );
            // ---- END TEMP ----

            return section;
        }

        // ---- TEMP: SDK-4523 ----
        private void TrackNativeTest()
        {
            var props = new Dictionary<string, object>
            {
                ["someNum"] = 123,
                ["someFloat"] = 3.14159,
                ["someString"] = "abc",
                ["someBool"] = true,
                ["someObject"] = new Dictionary<string, object>
                {
                    ["abc"] = "123",
                    ["nested"] = new Dictionary<string, object> { ["def"] = "456" },
                    ["ghi"] = null,
                },
                ["someArray"] = new List<object> { 1, 2 },
                ["someMixedArray"] = new List<object>
                {
                    1,
                    "2",
                    new Dictionary<string, object> { ["abc"] = "123" },
                    null,
                },
                ["someNull"] = null,
            };

            _viewModel.TrackEvent("props_native", props);
        }
        // ---- END TEMP ----
    }

to test props_native vs just the json parsing.

Unit / E2E

• The shared Appium spec at appium/tests/specs/10_event.spec.ts exercises track_event_button with this JSON. The E2E workflow added in this PR will run that spec against the demo on every PR going forward.

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing (Unity custom event property encoding + the E2E workflow that covers it)
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes (E2E suite via the new workflow)
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device

Final pass

• Code is as readable as possible
• I have reviewed this PR myself