Update test server to HTTPS and document OpenUPM publishing

- Update integration test host from phoenix-sharp.level3.io:3080 to
  phoenix-sharp.level3.io with wss:// and https:// protocols
- Document OpenUPM release flow and Unity package in CLAUDE.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Mazyod

CLAUDE.md

@@ -32,14 +32,20 @@ dotnet format
 - **Phoenix/** - Main library (netstandard2.0, C# 9.0, nullable enabled)
 - **PhoenixTests/** - NUnit tests (net9.0)
 - **Reference/** - Reference implementations for Unity (BestHTTP websocket, coroutine-based delayed executor)
+- **src/PhoenixSharp.Unity/** - Unity package project (published to OpenUPM as `io.level3.phoenixsharp`)
 
-## NuGet Package
+## Publishing
 
-The library is published to NuGet.org as `PhoenixSharp`.
+The library is distributed via two channels: **NuGet** (`PhoenixSharp`) and **OpenUPM** (`io.level3.phoenixsharp`). Both are published from a single trigger.
 
-**Publishing:** Handled automatically via GitHub Actions trusted publishing. To release:
-1. Create a GitHub release with a version tag (e.g., `v1.0.3`)
-2. The `publish.yml` workflow builds and pushes to NuGet.org
+**To release:**
+1. Create a GitHub release with a version tag (e.g., `v1.2.3`)
+2. The `publish.yml` workflow:
+   - Updates the Unity `package.json` version at `src/PhoenixSharp.Unity/Assets/Plugins/PhoenixSharp/package.json`
+   - Updates the README manifest example
+   - Commits and pushes the version bump back to `master`
+   - Builds and pushes the NuGet package via trusted publishing (OIDC)
+3. OpenUPM automatically detects the new git tag and publishes the Unity package from the `package.json`
 
 **Version management:** Version is set via git tag at release time. The `<Version>` in `Phoenix.csproj` is a fallback for local builds.
 
@@ -94,7 +100,7 @@ The library decouples from specific implementations via interfaces:
 
 Integration tests require a running Phoenix server. The test host is configured in `IntegrationTests.cs`:
 ```csharp
-private const string Host = "phoenix-sharp.level3.io:3080";
+private const string Host = "phoenix-sharp.level3.io";
 ```
 
 Server source: https://github.com/Mazyod/phoenix-integration-tester

PhoenixTests/IntegrationTests.cs

@@ -31,7 +31,7 @@ public void Log(LogLevel level, string source, string message)
     /// including socket connections, channel operations, presence tracking, and the async API.
     ///
     /// <para><b>Test Server:</b></para>
-    /// Tests connect to a Phoenix server at <c>phoenix-sharp.level3.io:3080</c>.
+    /// Tests connect to a Phoenix server at <c>phoenix-sharp.level3.io</c>.
     /// The server source code is available at: https://github.com/Mazyod/phoenix-integration-tester
     ///
     /// <para><b>Prerequisites:</b></para>
@@ -55,7 +55,7 @@ public class IntegrationTests
         [SetUp]
         public void Init()
         {
-            var address = $"http://{Host}/api/health-check";
+            var address = $"https://{Host}/api/health-check";
 
             // Verify server is available before running tests
             using HttpClient client = new();
@@ -72,7 +72,7 @@ public void Init()
         /// <summary>
         /// The Phoenix server host used for integration testing.
         /// </summary>
-        private const string Host = "phoenix-sharp.level3.io:3080";
+        private const string Host = "phoenix-sharp.level3.io";
 
         /// <summary>
         /// Default channel parameters used for authentication.
@@ -120,7 +120,7 @@ void OnCloseCallback(ushort code, string message)
                 onCloseData.Add(message);
             }
 
-            var socketAddress = $"ws://{Host}/socket";
+            var socketAddress = $"wss://{Host}/socket";
             var socketFactory = new DotNetWebSocketFactory();
             var socket = new Socket(
                 socketAddress,
@@ -361,7 +361,7 @@ void OnClosedCallback(ushort code, string reason)
                 onOpenCount--;
             }
 
-            var socketAddress = $"ws://{Host}/socket";
+            var socketAddress = $"wss://{Host}/socket";
             var socketFactory = new DotNetWebSocketFactory();
             var socket = new Socket(
                 socketAddress,
@@ -462,7 +462,7 @@ void OnOpenCallback()
                 onOpenCount++;
             }
 
-            var socketAddress = $"ws://{Host}/socket";
+            var socketAddress = $"wss://{Host}/socket";
             var socketFactory = new DotNetWebSocketFactory();
             var socket = new Socket(
                 socketAddress,
@@ -562,7 +562,7 @@ public async Task AsyncApiIntegrationTest()
         {
             // ===== SECTION: Socket Setup and ConnectAsync =====
 
-            var socketAddress = $"ws://{Host}/socket";
+            var socketAddress = $"wss://{Host}/socket";
             var socketFactory = new DotNetWebSocketFactory();
             var socket = new Socket(
                 socketAddress,
@@ -747,7 +747,7 @@ public async Task PresenceAsyncApiIntegrationTest()
         {
             // ===== SECTION: Socket Setup =====
 
-            var socketAddress = $"ws://{Host}/socket";
+            var socketAddress = $"wss://{Host}/socket";
             var socketFactory = new DotNetWebSocketFactory();
             var socket = new Socket(
                 socketAddress,