feat: letter-sound assessment event

pom-dependency-tree.txt

@@ -1,4 +1,4 @@
-ai.elimu:webapp:war:2.6.15-SNAPSHOT
+ai.elimu:webapp:war:2.6.16-SNAPSHOT
 +- ai.elimu:model:jar:model-2.0.97:compile
 |  \- com.google.code.gson:gson:jar:2.13.0:compile
 |     \- com.google.errorprone:error_prone_annotations:jar:2.37.0:compile

src/main/java/ai/elimu/entity/analytics/AssessmentEvent.java

@@ -0,0 +1,52 @@
+package ai.elimu.entity.analytics;
+
+import ai.elimu.entity.BaseEntity;
+import ai.elimu.entity.application.Application;
+import jakarta.persistence.Column;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.MappedSuperclass;
+import jakarta.persistence.Temporal;
+import jakarta.persistence.TemporalType;
+import jakarta.validation.constraints.NotNull;
+import java.util.Calendar;
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
+@MappedSuperclass
+public abstract class AssessmentEvent extends BaseEntity {
+
+  @NotNull
+  @Temporal(TemporalType.TIMESTAMP)
+  private Calendar timestamp;
+
+  /**
+   * See https://developer.android.com/reference/android/provider/Settings.Secure#ANDROID_ID
+   */
+  @NotNull
+  private String androidId;
+
+  /**
+   * The package name of the {@link #application} where the assessment event occurred.
+   */
+  @NotNull
+  private String packageName;
+
+  /**
+   * This field will only be populated if a corresponding {@link Application} can be found in the database for the {@link #packageName}.
+   */
+  @ManyToOne
+  private Application application;
+
+  /**
+   * Any additional data should be stored in the format of a JSON object.
+   * 
+   * Example:
+   * <pre>
+   * {'word_ids_presented': [1,2,3], 'word_id_selected': 2}
+   * </pre>
+   */
+  @Column(length = 1024)
+  private String additionalData;
+}