chore: deprecate standalone SecureStoreManager utility

Move SecureStoreManager project and tests to Deprecated folder and remove
from solution. SecureStore functionality is now integrated into ConfigManager.

Deprecated/JdeScoping.SecureStoreManager/Application/SecretUseCases.cs

@@ -0,0 +1,63 @@
+using Microsoft.Extensions.Logging;
+using JdeScoping.SecureStoreManager.Services;
+
+namespace JdeScoping.SecureStoreManager.Application;
+
+/// <summary>
+/// Secret CRUD use-case operations with logging.
+/// </summary>
+public class SecretUseCases
+{
+    private readonly ISecureStoreManager _storeManager;
+    private readonly ILogger<SecretUseCases> _logger;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="SecretUseCases"/> class.
+    /// </summary>
+    /// <param name="storeManager">The secure store manager.</param>
+    /// <param name="logger">The logger instance.</param>
+    public SecretUseCases(ISecureStoreManager storeManager, ILogger<SecretUseCases> logger)
+    {
+        _storeManager = storeManager ?? throw new ArgumentNullException(nameof(storeManager));
+        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+    }
+
+    /// <summary>
+    /// Sets a secret with the given key and value.
+    /// </summary>
+    /// <param name="key">The secret key.</param>
+    /// <param name="value">The secret value.</param>
+    public void SetSecret(string key, string value)
+    {
+        _logger.LogInformation("Setting secret {Key}", key);
+        _storeManager.SetSecret(key, value);
+    }
+
+    /// <summary>
+    /// Removes a secret by key.
+    /// </summary>
+    /// <param name="key">The secret key to remove.</param>
+    public void RemoveSecret(string key)
+    {
+        _logger.LogInformation("Removing secret {Key}", key);
+        _storeManager.RemoveSecret(key);
+    }
+
+    /// <summary>
+    /// Gets all keys in the current store.
+    /// </summary>
+    public IReadOnlyList<string> GetKeys()
+    {
+        return _storeManager.GetKeys();
+    }
+
+    /// <summary>
+    /// Gets the value of a secret by key.
+    /// </summary>
+    /// <param name="key">The secret key.</param>
+    /// <returns>The secret value.</returns>
+    public string GetSecret(string key)
+    {
+        return _storeManager.GetSecret(key);
+    }
+}