feat: Add unit tests and fakes for Crestron environment and data store

- Introduced `FakeCrestronEnvironment` and `FakeEthernetHelper` for testing purposes.
- Implemented `InMemoryCrestronDataStore` to facilitate unit tests for data storage.
- Created `DebugServiceTests` to validate the behavior of debug-related services.
- Added project files for unit tests targeting .NET 9.0 with necessary dependencies.
- Developed production adapters (`CrestronConsoleAdapter`, `CrestronDataStoreAdapter`, `CrestronEnvironmentAdapter`, `CrestronEthernetAdapter`) to interface with the Crestron SDK.
- Updated `Debug` class to utilize injected service abstractions instead of direct SDK calls.
- Enhanced `ControlSystem` initialization to register service adapters before usage.

src/PepperDash.Core.Tests/Fakes/CrestronConsoleFakes.cs

@@ -0,0 +1,38 @@
+using PepperDash.Core.Abstractions;
+
+namespace PepperDash.Core.Tests.Fakes;
+
+/// <summary>
+/// No-op ICrestronConsole that captures output for test assertions.
+/// </summary>
+public class CapturingCrestronConsole : ICrestronConsole
+{
+    public List<string> Lines { get; } = new();
+    public List<string> CommandResponses { get; } = new();
+    public List<(string Command, string HelpText)> RegisteredCommands { get; } = new();
+
+    public void PrintLine(string message) => Lines.Add(message);
+    public void Print(string message) => Lines.Add(message);
+    public void ConsoleCommandResponse(string message) => CommandResponses.Add(message);
+
+    public void AddNewConsoleCommand(
+        Action<string> callback,
+        string command,
+        string helpText,
+        ConsoleAccessLevel accessLevel)
+    {
+        RegisteredCommands.Add((command, helpText));
+    }
+}
+
+/// <summary>
+/// Minimal no-op ICrestronConsole that discards all output. Useful when you only
+/// care about the system under test and not what it logs.
+/// </summary>
+public class NoOpCrestronConsole : ICrestronConsole
+{
+    public void PrintLine(string message) { }
+    public void Print(string message) { }
+    public void ConsoleCommandResponse(string message) { }
+    public void AddNewConsoleCommand(Action<string> _, string __, string ___, ConsoleAccessLevel ____) { }
+}