feat: add generation source handling for task creation and updates

backend/src/main/kotlin/com/condado/newsletter/model/EntityTask.kt

@@ -3,6 +3,8 @@ package com.condado.newsletter.model
 import jakarta.persistence.CascadeType
 import jakarta.persistence.Column
 import jakarta.persistence.Entity
+import jakarta.persistence.EnumType
+import jakarta.persistence.Enumerated
 import jakarta.persistence.FetchType
 import jakarta.persistence.GeneratedValue
 import jakarta.persistence.GenerationType
@@ -37,6 +39,10 @@ class EntityTask(
     @Column(name = "email_lookback", nullable = false)
     val emailLookback: String,
 
+    @Enumerated(EnumType.STRING)
+    @Column(name = "generation_source", nullable = false)
+    val generationSource: TaskGenerationSource = TaskGenerationSource.LLAMA,
+
     @Column(nullable = false)
     val active: Boolean = true,