refactor(cleanup-03): delete ApprovalReducer and simplify RootReducer

Remove the approvalAction/NoOp wrong-scope filter and the ApprovalReducer
call site from RootReducer. approvalJustArrived is now derived from the
selected session's pendingApproval delta. Delete ApprovalReducer.kt,
ApprovalState.kt, and ApprovalReducerTest.kt; approval truth is
structurally owned by SessionSummary.

apps/tui/src/main/kotlin/com/correx/apps/tui/reducer/ApprovalReducer.kt

@@ -1,58 +0,0 @@
-package com.correx.apps.tui.reducer
-
-import com.correx.apps.server.protocol.ApprovalDecision
-import com.correx.apps.server.protocol.ClientMessage
-import com.correx.apps.tui.input.Action
-import com.correx.apps.tui.state.ApprovalState
-import com.correx.apps.tui.state.InputMode
-import com.correx.core.events.types.ApprovalRequestId
-
-object ApprovalReducer {
-    fun reduce(
-        approval: ApprovalState,
-        inputMode: InputMode,
-        action: Action,
-    ): Pair<ApprovalState, List<Effect>> = when (action) {
-        is Action.ApproveActive -> {
-            val active = approval.active
-            if (active != null) {
-                ApprovalState(active = null) to listOf(
-                    Effect.SendWs(
-                        ClientMessage.ApprovalResponse(
-                            requestId = ApprovalRequestId(active.requestId),
-                            decision = ApprovalDecision.APPROVE,
-                            steeringNote = null,
-                        ),
-                    ),
-                )
-            } else {
-                approval to emptyList()
-            }
-        }
-
-        is Action.RejectActive -> {
-            val active = approval.active
-            if (active != null) {
-                ApprovalState(active = null) to listOf(
-                    Effect.SendWs(
-                        ClientMessage.ApprovalResponse(
-                            requestId = ApprovalRequestId(active.requestId),
-                            decision = ApprovalDecision.REJECT,
-                            steeringNote = null,
-                        ),
-                    ),
-                )
-            } else {
-                approval to emptyList()
-            }
-        }
-
-        is Action.SubmitInput -> if (inputMode == InputMode.STEER) {
-            ApprovalState(active = null) to emptyList()
-        } else {
-            approval to emptyList()
-        }
-
-        else -> approval to emptyList()
-    }
-}

apps/tui/src/main/kotlin/com/correx/apps/tui/reducer/RootReducer.kt

@@ -2,7 +2,6 @@ package com.correx.apps.tui.reducer
 
 import com.correx.apps.server.protocol.ServerMessage
 import com.correx.apps.tui.input.Action
-import com.correx.apps.tui.state.ApprovalState
 import com.correx.apps.tui.state.TuiState
 import org.slf4j.LoggerFactory
 
@@ -46,33 +45,22 @@ object RootReducer {
         val quitEffects: List<Effect> = if (action is Action.Quit) listOf(Effect.Quit) else emptyList()
         val prevInputMode = state.inputMode
         val prevInputBuffer = state.inputBuffer
-        val approvalAction = if (
-            action is Action.ServerEventReceived &&
-            action.message is ServerMessage.SessionSnapshot &&
-            action.message.sessionId.value != state.sessions.selectedId
-        ) Action.NoOp else action
 
         log.debug("input state before reducers={}", state.input)
         val (afterInput, ie) = InputReducer.reduce(state, action)
         log.debug("sessions state before reducers={}", state.sessions)
         val (sessions, se) = SessionsReducer.reduce(afterInput.sessions, prevInputMode, prevInputBuffer, action, clock)
-        val selectedId = afterInput.sessions.selectedId
-        val bridgedApproval = ApprovalState(
-            active = afterInput.sessions.sessions.find { it.id == selectedId }?.pendingApproval,
-        )
-        val (approval, ae) = ApprovalReducer.reduce(bridgedApproval, prevInputMode, approvalAction)
-        val approvalJustArrived = approval.active != null && bridgedApproval.active == null
-        val sessionsWithApproval = sessions.copy(
-            sessions = sessions.sessions.map { s ->
-                if (s.id == selectedId) s.copy(pendingApproval = approval.active) else s
-            },
-        )
         log.debug("connection state before reducers={}", state.connection)
         val (connection, ce) = ConnectionReducer.reduce(afterInput.connection, action)
         log.debug("provider state before reducers={}", state.provider)
         val (provider, pe) = ProviderReducer.reduce(afterInput.provider, action)
+
+        val selectedPending = sessions.sessions.firstOrNull { it.id == sessions.selectedId }?.pendingApproval
+        val prevSelectedPending = afterInput.sessions.sessions.firstOrNull { it.id == afterInput.sessions.selectedId }?.pendingApproval
+        val approvalJustArrived = selectedPending != null && prevSelectedPending == null
+
         val withSubReducers = afterInput.copy(
-            sessions = sessionsWithApproval,
+            sessions = sessions,
             connection = connection,
             provider = provider,
             approvalOverlayVisible = if (approvalJustArrived) true else afterInput.approvalOverlayVisible,
@@ -90,6 +78,6 @@ object RootReducer {
 
             else -> withSubReducers
         }
-        return final to (quitEffects + ie + se + ae + ce + pe)
+        return final to (quitEffects + ie + se + ce + pe)
     }
 }

apps/tui/src/main/kotlin/com/correx/apps/tui/state/ApprovalState.kt

@@ -1,5 +0,0 @@
-package com.correx.apps.tui.state
-
-data class ApprovalState(
-    val active: ApprovalInfo? = null,
-)

apps/tui/src/test/kotlin/com/correx/apps/tui/reducer/ApprovalReducerTest.kt

@@ -1,86 +0,0 @@
-package com.correx.apps.tui.reducer
-
-import com.correx.apps.server.protocol.ApprovalDecision
-import com.correx.apps.server.protocol.ClientMessage
-import com.correx.apps.tui.input.Action
-import com.correx.apps.tui.state.ApprovalInfo
-import com.correx.apps.tui.state.ApprovalState
-import com.correx.apps.tui.state.InputMode
-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 ApprovalReducerTest {
-
-    private val activeInfo = ApprovalInfo(
-        requestId = "req-1",
-        sessionId = "sess-1",
-        tier = "HIGH",
-        riskSummary = "HIGH",
-        toolName = "bash",
-        preview = null,
-    )
-
-    private fun reduce(
-        approval: ApprovalState = ApprovalState(),
-        inputMode: InputMode = InputMode.ROUTER,
-        action: Action,
-    ) = ApprovalReducer.reduce(approval, inputMode, action)
-
-    @Test
-    fun `ApproveActive emits APPROVE response and clears active`() {
-        val (state, effects) = reduce(
-            approval = ApprovalState(active = activeInfo),
-            action = Action.ApproveActive,
-        )
-        assertNull(state.active)
-        assertEquals(1, effects.size)
-        val effect = effects[0] as Effect.SendWs
-        val msg = effect.message as ClientMessage.ApprovalResponse
-        assertEquals(ApprovalDecision.APPROVE, msg.decision)
-        assertEquals("req-1", msg.requestId.value)
-        assertNull(msg.steeringNote)
-    }
-
-    @Test
-    fun `ApproveActive with no active approval is no-op`() {
-        val (state, effects) = reduce(action = Action.ApproveActive)
-        assertNull(state.active)
-        assertTrue(effects.isEmpty())
-    }
-
-    @Test
-    fun `RejectActive emits REJECT response and clears active`() {
-        val (state, effects) = reduce(
-            approval = ApprovalState(active = activeInfo),
-            action = Action.RejectActive,
-        )
-        assertNull(state.active)
-        assertEquals(1, effects.size)
-        val effect = effects[0] as Effect.SendWs
-        val msg = effect.message as ClientMessage.ApprovalResponse
-        assertEquals(ApprovalDecision.REJECT, msg.decision)
-    }
-
-    @Test
-    fun `SubmitInput in SteeringNote mode clears active approval`() {
-        val (state, effects) = reduce(
-            approval = ApprovalState(active = activeInfo),
-            inputMode = InputMode.STEER,
-            action = Action.SubmitInput,
-        )
-        assertNull(state.active)
-        assertTrue(effects.isEmpty())
-    }
-
-    @Test
-    fun `SubmitInput in non-SteeringNote mode is no-op`() {
-        val (state, _) = reduce(
-            approval = ApprovalState(active = activeInfo),
-            inputMode = InputMode.NAVIGATE,
-            action = Action.SubmitInput,
-        )
-        assertEquals(activeInfo, state.active)
-    }
-}

apps/tui/src/test/kotlin/com/correx/apps/tui/reducer/RootReducerTest.kt

@@ -1,10 +1,17 @@
 package com.correx.apps.tui.reducer
 
 import com.correx.apps.server.protocol.ClientMessage
+import com.correx.apps.server.protocol.RiskSummaryDto
+import com.correx.apps.server.protocol.ServerMessage
 import com.correx.apps.tui.input.Action
 import com.correx.apps.tui.state.ConnectionState
 import com.correx.apps.tui.state.InputMode
+import com.correx.apps.tui.state.SessionSummary
+import com.correx.apps.tui.state.SessionsState
 import com.correx.apps.tui.state.TuiState
+import com.correx.core.approvals.Tier
+import com.correx.core.events.types.ApprovalRequestId
+import com.correx.core.events.types.SessionId
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertTrue
 import org.junit.jupiter.api.Test
@@ -138,4 +145,48 @@ class RootReducerTest {
         val (s2, _) = RootReducer.reduce(s1, Action.Backspace, fixedClock)
         assertEquals("ab", s2.inputBuffer)
     }
+
+    private fun approvalRequiredMsg(sessionId: String, requestId: String = "r1") =
+        ServerMessage.ApprovalRequired(
+            sessionId = SessionId(sessionId),
+            requestId = ApprovalRequestId(requestId),
+            tier = Tier.T2,
+            riskSummary = RiskSummaryDto(level = "HIGH", factors = emptyList(), recommendedAction = "review"),
+            toolName = "bash",
+            preview = null,
+            sequence = 1L,
+            sessionSequence = 1L,
+        )
+
+    private fun session(id: String) = SessionSummary(id = id, status = "ACTIVE", workflowId = "wf", lastEventAt = 0L)
+
+    @Test
+    fun `ApprovalRequired on selected session auto-opens approvalOverlayVisible`() {
+        val initial = TuiState(
+            snapshotPhase = false,
+            sessions = SessionsState(sessions = listOf(session("s1")), selectedId = "s1"),
+        )
+        val (state, _) = RootReducer.reduce(
+            initial, Action.ServerEventReceived(approvalRequiredMsg("s1")), fixedClock,
+        )
+        assertEquals(true, state.approvalOverlayVisible)
+        assertEquals("r1", state.sessions.sessions[0].pendingApproval?.requestId)
+    }
+
+    @Test
+    fun `ApprovalRequired on non-selected session does not open approvalOverlayVisible`() {
+        val initial = TuiState(
+            snapshotPhase = false,
+            sessions = SessionsState(
+                sessions = listOf(session("s1"), session("s2")),
+                selectedId = "s1",
+            ),
+        )
+        val (state, _) = RootReducer.reduce(
+            initial, Action.ServerEventReceived(approvalRequiredMsg("s2")), fixedClock,
+        )
+        assertEquals(false, state.approvalOverlayVisible)
+        assertEquals(null, state.sessions.sessions.find { it.id == "s1" }?.pendingApproval)
+        assertEquals("r1", state.sessions.sessions.find { it.id == "s2" }?.pendingApproval?.requestId)
+    }
 }