refactor: reorganize Application layer into folder structure

src/GreenHome.Application/Interfaces/IAIQueryService.cs

@@ -0,0 +1,39 @@
+using GreenHome.Domain;
+
+namespace GreenHome.Application;
+
+/// <summary>
+/// Service for managing AI queries and their history
+/// </summary>
+public interface IAIQueryService
+{
+    /// <summary>
+    /// Saves an AI query to the database
+    /// </summary>
+    Task<AIQuery> SaveQueryAsync(AIQuery query, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets AI query history for a specific device
+    /// </summary>
+    Task<List<AIQuery>> GetDeviceQueriesAsync(int deviceId, int take = 50, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets AI query history for a specific user
+    /// </summary>
+    Task<List<AIQuery>> GetUserQueriesAsync(int userId, int take = 50, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets total token usage for a device
+    /// </summary>
+    Task<int> GetDeviceTotalTokensAsync(int deviceId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets total token usage for a user
+    /// </summary>
+    Task<int> GetUserTotalTokensAsync(int userId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets AI query statistics (totals, averages, today's usage)
+    /// </summary>
+    Task<AIQueryStats> GetStatsAsync(CancellationToken cancellationToken = default);
+}