feat(kernel): retried stages receive explicit failure feedback; default retry backoff 1s

core/events/src/main/kotlin/com/correx/core/events/execution/RetryPolicy.kt

@@ -5,7 +5,7 @@ import kotlinx.serialization.Serializable
 @Serializable
 data class RetryPolicy(
     val maxAttempts: Int,
-    val backoffMs: Long = 0L,
+    val backoffMs: Long = 1_000L,
 ) {
     init {
         require(maxAttempts >= 1) { "maxAttempts must be >= 1" }

core/kernel/src/main/kotlin/com/correx/core/kernel/orchestration/ContextFeedback.kt

@@ -6,10 +6,32 @@ package com.correx.core.kernel.orchestration
 import com.correx.core.context.model.ContextEntry
 import com.correx.core.context.model.ContextLayer
 import com.correx.core.context.model.EntryRole
+import com.correx.core.events.events.RetryAttemptedEvent
+import com.correx.core.events.events.StoredEvent
 import com.correx.core.events.types.ContextEntryId
+import com.correx.core.events.types.StageId
 import com.correx.core.sessions.BoundProjectProfile
 import java.util.UUID
 
+fun buildRetryFeedbackEntry(events: List<StoredEvent>, stageId: StageId): ContextEntry? {
+    val latest = events
+        .mapNotNull { it.payload as? RetryAttemptedEvent }
+        .lastOrNull { it.stageId == stageId } ?: return null
+    val content = "## Retry feedback\n" +
+        "Attempt ${latest.attemptNumber} of ${latest.maxAttempts} for stage '${stageId.value}'. " +
+        "The previous attempt failed: ${latest.failureReason}\n" +
+        "Address the failure cause directly. Do not repeat the identical approach."
+    return ContextEntry(
+        id = ContextEntryId(UUID.randomUUID().toString()),
+        layer = ContextLayer.L1,
+        content = content,
+        sourceType = "retryFeedback",
+        sourceId = stageId.value,
+        tokenEstimate = content.length / 4,
+        role = EntryRole.SYSTEM,
+    )
+}
+
 fun buildProjectProfileEntry(profile: BoundProjectProfile): ContextEntry {
     val content = buildString {
         append("## Project profile\n")

core/kernel/src/main/kotlin/com/correx/core/kernel/orchestration/SessionOrchestrator.kt

@@ -365,9 +365,11 @@ abstract class SessionOrchestrator(
             } ?: emptyList()
         val projectProfileEntries = session.state.boundProjectProfile
             ?.let { listOf(buildProjectProfileEntry(it)) } ?: emptyList()
+        val retryFeedbackEntries = buildRetryFeedbackEntry(eventStore.read(sessionId), stageId)
+            ?.let { listOf(it) } ?: emptyList()
         var accumulatedEntries =
             systemPrompt + profileEntries + projectProfileEntries + journalEntries + repoMapEntries +
-                needsEntries + schemaEntries + promptEntries + steeringEntries
+                needsEntries + schemaEntries + promptEntries + steeringEntries + retryFeedbackEntries
         val contextPack = contextPackBuilder.build(
             id = ContextPackId(UUID.randomUUID().toString()),
             sessionId = sessionId,

testing/contracts/src/test/kotlin/com/correx/testing/contracts/model/orchestration/RetryPolicyTest.kt

@@ -28,9 +28,9 @@ class RetryPolicyTest {
     }
 
     @Test
-    fun `backoffMs defaults to zero`() {
+    fun `backoffMs defaults to one second`() {
         val policy = RetryPolicy(maxAttempts = 1)
-        assertEquals(0L, policy.backoffMs)
+        assertEquals(1_000L, policy.backoffMs)
     }
 
     @Test

testing/kernel/src/test/kotlin/ContextFeedbackTest.kt

@@ -1,13 +1,47 @@
 import com.correx.core.context.model.ContextLayer
 import com.correx.core.context.model.EntryRole
+import com.correx.core.events.events.RetryAttemptedEvent
+import com.correx.core.events.types.SessionId
+import com.correx.core.events.types.StageId
 import com.correx.core.kernel.orchestration.buildProjectProfileEntry
+import com.correx.core.kernel.orchestration.buildRetryFeedbackEntry
 import com.correx.core.sessions.BoundProjectProfile
+import com.correx.testing.fixtures.EventFixtures.stored
 import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
 import org.junit.jupiter.api.Assertions.assertTrue
 import org.junit.jupiter.api.Test
 
 class ContextFeedbackTest {
 
+    @Test
+    fun `no retry events yields null`() {
+        assertNull(buildRetryFeedbackEntry(emptyList(), StageId("impl")))
+    }
+
+    @Test
+    fun `latest retry event for the stage becomes a labeled L1 system entry`() {
+        val events = listOf(
+            stored(payload = RetryAttemptedEvent(SessionId("s"), StageId("impl"), 1, 3, "old reason")),
+            stored(payload = RetryAttemptedEvent(SessionId("s"), StageId("other"), 1, 3, "other stage")),
+            stored(payload = RetryAttemptedEvent(SessionId("s"), StageId("impl"), 2, 3, "tests failed: NPE in FooTest")),
+        )
+        val entry = buildRetryFeedbackEntry(events, StageId("impl"))!!
+        assertEquals("retryFeedback", entry.sourceType)
+        assertEquals(ContextLayer.L1, entry.layer)
+        assertEquals(EntryRole.SYSTEM, entry.role)
+        assertTrue(entry.content.contains("Attempt 2 of 3"), "content: ${entry.content}")
+        assertTrue(entry.content.contains("tests failed: NPE in FooTest"), "content: ${entry.content}")
+    }
+
+    @Test
+    fun `retry entry for other stage is not returned for queried stage`() {
+        val events = listOf(
+            stored(payload = RetryAttemptedEvent(SessionId("s"), StageId("other"), 1, 3, "reason")),
+        )
+        assertNull(buildRetryFeedbackEntry(events, StageId("impl")))
+    }
+
     @Test
     fun `project profile renders as single L0 entry`() {
         val entry = buildProjectProfileEntry(