[APPFW] Implement Team Application C# Interface

- Implement Interop, Wrapper Class to implement C# Team Application
- Add OnCreate Error Handling
- When the application start, TeamManager will hold the application
  instance to guarantee the object alive until exit.
- Implement TeamViewApplication

Signed-off-by: Jihoi Kim <jihoi.kim@samsung.com>

Author: newb1e-kim

src/Tizen.Applications.Team/CultureInfoHelper.cs

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2026 Samsung Electronics Co., Ltd All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the License);
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using System;
+using System.IO;
+using System.Runtime.InteropServices;
+
+namespace Tizen.Applications
+{
+    internal static class CultureInfoHelper
+    {
+        private const string _pathCultureInfoIni = "/usr/share/dotnet.tizen/framework/i18n/CultureInfo.ini";
+        private static bool _fileExists = File.Exists(_pathCultureInfoIni);
+
+        public static string GetCultureName(string locale)
+        {
+            if (!_fileExists)
+            {
+                return string.Empty;
+            }
+
+            IntPtr dictionary = Interop.LibIniParser.Load(_pathCultureInfoIni);
+            if (dictionary == IntPtr.Zero)
+            {
+                return string.Empty;
+            }
+
+            string cultureName = string.Empty;
+#pragma warning disable CA1308
+            string key = "CultureInfo:" + locale.ToLowerInvariant();
+#pragma warning restore CA1308
+            IntPtr value = Interop.LibIniParser.GetString(dictionary, key, IntPtr.Zero);
+            if (value != IntPtr.Zero)
+            {
+                cultureName = Marshal.PtrToStringAnsi(value);
+            }
+
+            Interop.LibIniParser.FreeDict(dictionary);
+            return cultureName;
+        }
+    }
+}

src/Tizen.Applications.Team/GSourceManager.cs

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2026 Samsung Electronics Co., Ltd All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the License);
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using System;
+using System.Collections.Concurrent;
+
+namespace Tizen.Applications
+{
+    internal static class GSourceManager
+    {
+        private static readonly GSourceContext _tizenContext = new GSourceContext();
+        private static readonly GSourceContext _tizenUIContext = new GSourceContext();
+        private static readonly Interop.Glib.GSourceFunc _wrapperHandler = new Interop.Glib.GSourceFunc(Handler);
+
+        public static void Post(Action action)
+        {
+            IntPtr context = IntPtr.Zero;
+            var sourceContext = context == IntPtr.Zero ? _tizenContext : _tizenUIContext;
+            sourceContext.Post(action, context, _wrapperHandler);
+        }
+
+        private static bool Handler(IntPtr userData)
+        {
+            var sourceContext = userData == IntPtr.Zero ? _tizenContext : _tizenUIContext;
+            return sourceContext.ProcessQueue();
+        }
+    }
+
+    internal class GSourceContext
+    {
+        private readonly ConcurrentQueue<Action> _actionQueue = new ConcurrentQueue<Action>();
+        private readonly object _lock = new object();
+        private IntPtr _source = IntPtr.Zero;
+
+        public void Post(Action action, IntPtr context, Interop.Glib.GSourceFunc handler)
+        {
+            _actionQueue.Enqueue(action);
+
+            lock (_lock)
+            {
+                if (_source != IntPtr.Zero)
+                {
+                    return;
+                }
+
+                _source = Interop.Glib.IdleSourceNew();
+                Interop.Glib.SourceSetCallback(_source, handler, context, IntPtr.Zero);
+                _ = Interop.Glib.SourceAttach(_source, context);
+                Interop.Glib.SourceUnref(_source);
+            }
+        }
+
+        public bool ProcessQueue()
+        {
+            if (_actionQueue.TryDequeue(out var action))
+            {
+                action?.Invoke();
+            }
+
+            lock (_lock)
+            {
+                if (!_actionQueue.IsEmpty)
+                {
+                    return true;
+                }
+
+                _source = IntPtr.Zero;
+            }
+
+            return false;
+        }
+    }
+}