fix(sessions): terminalize session on workflow completion

DefaultSessionReducer skipped WorkflowCompletedEvent to avoid terminalizing on freestyle planning's mid-session completion, but that left execution/normal completions stuck ACTIVE forever — headless watchers and approval loops never saw a terminal state. Add workflowId to WorkflowCompletedEvent (defaulted for replay compat), pass graph.id at all completeWorkflow sites, and terminalize to COMPLETED unless it's the freestyle_planning handoff. Correct stale tests that pinned the ACTIVE-forever behavior.

core/sessions/src/main/kotlin/com/correx/core/sessions/DefaultSessionReducer.kt

@@ -8,8 +8,13 @@ import com.correx.core.events.events.StageCompletedEvent
 import com.correx.core.events.events.StageFailedEvent
 import com.correx.core.events.events.StoredEvent
 import com.correx.core.events.events.TransitionExecutedEvent
+import com.correx.core.events.events.WorkflowCompletedEvent
 import com.correx.core.events.events.WorkflowFailedEvent
 
+// The freestyle two-phase planning workflow. Its completion hands off to the execution workflow
+// rather than ending the session, so it must not terminalize (see reduce()).
+private const val PLANNING_WORKFLOW_ID = "freestyle_planning"
+
 class DefaultSessionReducer : SessionReducer {
 
     override fun reduce(
@@ -24,13 +29,19 @@ class DefaultSessionReducer : SessionReducer {
                 SessionStatus.FAILED
 
             // A failed workflow is terminal for the session: no current workflow recovers after
-            // one fails (freestyle's planning→execution handoff only fires on WorkflowCompleted).
-            // Without this, an exhausted-retry WorkflowFailed left the session ACTIVE forever, so
-            // clients/approval loops never saw a terminal state. WorkflowCompleted is deliberately
-            // NOT mapped here — planning emits its own mid-session, so it isn't session-terminal.
+            // one fails.
             is WorkflowFailedEvent ->
                 SessionStatus.FAILED
 
+            // A completed workflow is session-terminal EXCEPT the freestyle planning workflow, which
+            // completes mid-session and hands off to the execution workflow (the handoff fires on
+            // planning's WorkflowCompleted — see ServerModule). Terminalizing on it would falsely mark
+            // the session done during the planning→execution gap; leaving it ACTIVE lets the real
+            // (execution) completion terminalize. Without this, a normal single-workflow session — and
+            // the execution phase — stayed ACTIVE forever, so clients/approval loops never saw done.
+            is WorkflowCompletedEvent ->
+                if (payload.workflowId == PLANNING_WORKFLOW_ID) state.status else SessionStatus.COMPLETED
+
             is StageCompletedEvent,
             is TransitionExecutedEvent ->
                 SessionStatus.ACTIVE

core/sessions/src/test/kotlin/com/correx/core/sessions/DefaultSessionReducerTest.kt

@@ -70,6 +70,32 @@ class DefaultSessionReducerTest {
         assertEquals(SessionStatus.FAILED, reducer.reduce(initialState, event).status)
     }
 
+    @Test
+    fun `WorkflowCompletedEvent flips session status to COMPLETED`() {
+        val event = stored(
+            com.correx.core.events.events.WorkflowCompletedEvent(
+                sessionId = sessionId,
+                terminalStageId = com.correx.core.events.types.StageId("report"),
+                totalStages = 3,
+                workflowId = "review_loop",
+            ),
+        )
+        assertEquals(SessionStatus.COMPLETED, reducer.reduce(initialState, event).status)
+    }
+
+    @Test
+    fun `WorkflowCompletedEvent for freestyle planning stays ACTIVE (hands off to execution)`() {
+        val event = stored(
+            com.correx.core.events.events.WorkflowCompletedEvent(
+                sessionId = sessionId,
+                terminalStageId = com.correx.core.events.types.StageId("architect"),
+                totalStages = 2,
+                workflowId = "freestyle_planning",
+            ),
+        )
+        assertEquals(SessionStatus.ACTIVE, reducer.reduce(initialState, event).status)
+    }
+
     @Test
     fun `unrelated event leaves boundProfile unchanged`() {
         val state = initialState.copy(