feat(News): refactor news service and add sentiment tracking

FinlyticNews/Entities/MatchedAssetEntity.cs

@@ -0,0 +1,40 @@
+using System.ComponentModel.DataAnnotations;
+using System.Text.Json.Serialization;
+
+namespace FinlyticNews.Entities;
+
+/// <summary>
+/// Represents a specific financial asset class match linked to a news article.
+/// </summary>
+public class MatchedAssetEntity
+{
+    /// <summary>
+    /// Gets or sets the unique primary key identifier.
+    /// </summary>
+    [Key]
+    public Guid Id { get; set; } = Guid.NewGuid();
+
+    /// <summary>
+    /// Gets or sets the foreign key pointing to the associated news article.
+    /// </summary>
+    [Required]
+    public Guid NewsArticleId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the navigation property for the associated news article.
+    /// </summary>
+    [JsonIgnore]
+    public NewsArticleEntity? NewsArticle { get; set; }
+
+    /// <summary>
+    /// Gets or sets the ISIN of the matched asset.
+    /// </summary>
+    [Required]
+    public string Isin { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the matched asset name.
+    /// </summary>
+    [Required]
+    public string Name { get; set; } = string.Empty;
+}