epic-12: after epic audit and init commit

core/artifacts/build.gradle

@@ -0,0 +1,9 @@
+plugins {
+    id 'java-library'
+    id 'org.jetbrains.kotlin.jvm'
+    id 'org.jetbrains.kotlin.plugin.serialization'
+}
+
+dependencies {
+    implementation(project(":core:events"))
+}

core/artifacts/src/main/kotlin/com/correx/core/artifacts/ArtifactProjector.kt

@@ -0,0 +1,24 @@
+package com.correx.core.artifacts
+
+import com.correx.core.events.events.StoredEvent
+import com.correx.core.sessions.projections.Projection
+import java.util.logging.Logger
+
+class ArtifactProjector(private val reducer: ArtifactReducer) : Projection<ArtifactState> {
+
+    private val logger: Logger = Logger.getLogger(ArtifactProjector::class.java.name)
+
+    override fun initial(): ArtifactState = ArtifactState()
+
+    // Invalid lifecycle transitions must not crash the replayer. Log and leave state unchanged
+    // so replay continues; the event log remains the source of truth.
+    override fun apply(state: ArtifactState, event: StoredEvent): ArtifactState =
+        reducer.reduce(state, event).getOrElse { exception ->
+            if (exception !is IllegalStateException) throw exception
+            logger.warning(
+                "Invalid artifact lifecycle transition (event payload=${event.payload::class.simpleName}): " +
+                    "${exception.message}. State unchanged."
+            )
+            state
+        }
+}

core/artifacts/src/main/kotlin/com/correx/core/artifacts/ArtifactReducer.kt

@@ -0,0 +1,77 @@
+package com.correx.core.artifacts
+
+import com.correx.core.artifacts.model.ArtifactRelationship
+import com.correx.core.events.events.ArtifactArchivedEvent
+import com.correx.core.events.events.ArtifactCreatedEvent
+import com.correx.core.events.events.ArtifactRejectedEvent
+import com.correx.core.events.events.ArtifactRelationshipAddedEvent
+import com.correx.core.events.events.ArtifactSupersededEvent
+import com.correx.core.events.events.ArtifactValidatedEvent
+import com.correx.core.events.events.ArtifactValidatingEvent
+import com.correx.core.events.events.StoredEvent
+import com.correx.core.events.types.ArtifactLifecyclePhase
+
+interface ArtifactReducer {
+    fun reduce(state: ArtifactState, event: StoredEvent): Result<ArtifactState>
+}
+
+class DefaultArtifactReducer : ArtifactReducer {
+
+    override fun reduce(state: ArtifactState, event: StoredEvent): Result<ArtifactState> =
+        when (val p = event.payload) {
+            is ArtifactCreatedEvent ->
+                Result.success(state.copy(phase = ArtifactLifecyclePhase.CREATED))
+            is ArtifactValidatingEvent ->
+                transition(state, ArtifactLifecyclePhase.VALIDATING, ArtifactLifecyclePhase.CREATED)
+            is ArtifactValidatedEvent ->
+                transition(state, ArtifactLifecyclePhase.VALIDATED, ArtifactLifecyclePhase.VALIDATING)
+            is ArtifactRejectedEvent ->
+                transition(state, ArtifactLifecyclePhase.REJECTED, ArtifactLifecyclePhase.VALIDATING)
+            is ArtifactSupersededEvent ->
+                transition(state, ArtifactLifecyclePhase.SUPERSEDED, ArtifactLifecyclePhase.VALIDATED)
+            is ArtifactArchivedEvent ->
+                transitionFromAny(
+                    state,
+                    ArtifactLifecyclePhase.ARCHIVED,
+                    ArtifactLifecyclePhase.VALIDATED,
+                    ArtifactLifecyclePhase.REJECTED,
+                )
+            is ArtifactRelationshipAddedEvent -> {
+                val rel = ArtifactRelationship(p.sourceId, p.targetId, p.relationshipType)
+                Result.success(
+                    state.copy(lineage = state.lineage.copy(relationships = state.lineage.relationships + rel))
+                )
+            }
+            else -> Result.success(state)
+        }
+
+    private fun transition(
+        state: ArtifactState,
+        to: ArtifactLifecyclePhase,
+        from: ArtifactLifecyclePhase,
+    ): Result<ArtifactState> =
+        if (state.phase == from) {
+            Result.success(state.copy(phase = to))
+        } else {
+            Result.failure(
+                IllegalStateException(
+                    "Invalid artifact transition: ${state.phase} → $to (expected $from)"
+                )
+            )
+        }
+
+    private fun transitionFromAny(
+        state: ArtifactState,
+        to: ArtifactLifecyclePhase,
+        vararg validFrom: ArtifactLifecyclePhase,
+    ): Result<ArtifactState> =
+        if (state.phase in validFrom) {
+            Result.success(state.copy(phase = to))
+        } else {
+            Result.failure(
+                IllegalStateException(
+                    "Invalid artifact transition: ${state.phase} → $to (expected one of ${validFrom.toList()})"
+                )
+            )
+        }
+}

core/artifacts/src/main/kotlin/com/correx/core/artifacts/ArtifactState.kt

@@ -0,0 +1,11 @@
+package com.correx.core.artifacts
+
+import com.correx.core.artifacts.model.ArtifactLineage
+import com.correx.core.events.types.ArtifactLifecyclePhase
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ArtifactState(
+    val phase: ArtifactLifecyclePhase = ArtifactLifecyclePhase.CREATED,
+    val lineage: ArtifactLineage = ArtifactLineage()
+)

core/artifacts/src/main/kotlin/com/correx/core/artifacts/Module.kt

@@ -0,0 +1,3 @@
+package com.correx.core.artifacts
+
+object Module

core/artifacts/src/main/kotlin/com/correx/core/artifacts/model/Artifact.kt

@@ -0,0 +1,20 @@
+package com.correx.core.artifacts.model
+
+import com.correx.core.events.types.ArtifactId
+import com.correx.core.events.types.ArtifactLifecyclePhase
+import com.correx.core.events.types.SessionId
+import com.correx.core.events.types.StageId
+import kotlinx.datetime.Instant
+import kotlinx.serialization.Serializable
+
+@Serializable
+sealed interface Artifact {
+    val id: ArtifactId
+    val sessionId: SessionId
+    val stageId: StageId
+    val schemaVersion: Int
+    val createdAt: Instant
+    val lifecyclePhase: ArtifactLifecyclePhase
+    val lineage: ArtifactLineage
+    val metadata: Map<String, String>
+}

core/artifacts/src/main/kotlin/com/correx/core/artifacts/model/ArtifactLineage.kt

@@ -0,0 +1,12 @@
+package com.correx.core.artifacts.model
+
+import com.correx.core.events.types.ArtifactId
+import com.correx.core.events.types.ValidationReportId
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ArtifactLineage(
+    val parentIds: List<ArtifactId> = emptyList(),
+    val relationships: List<ArtifactRelationship> = emptyList(),
+    val validationReportIds: List<ValidationReportId> = emptyList()
+)

core/artifacts/src/main/kotlin/com/correx/core/artifacts/model/ArtifactRelationship.kt

@@ -0,0 +1,12 @@
+package com.correx.core.artifacts.model
+
+import com.correx.core.events.types.ArtifactId
+import com.correx.core.events.types.ArtifactRelationshipType
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ArtifactRelationship(
+    val sourceId: ArtifactId,
+    val targetId: ArtifactId,
+    val type: ArtifactRelationshipType
+)

core/artifacts/src/main/kotlin/com/correx/core/artifacts/serialization/ArtifactSerializationModule.kt

@@ -0,0 +1,11 @@
+package com.correx.core.artifacts.serialization
+
+import com.correx.core.artifacts.model.Artifact
+import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.polymorphic
+
+val artifactModule: SerializersModule = SerializersModule {
+    polymorphic(Artifact::class) {
+        // concrete artifact subclasses registered here in future epics
+    }
+}