fix(tui): undo pending session input

packages/app/src/context/server-session-v2-reducer.test.ts

@@ -153,4 +153,42 @@ describe("v2 session reducer", () => {
 
     expect(result).toMatchObject({ sessionID: "ses_1", missing: "msg_user", touched: [] })
   })
+
+  test("forgets withdrawn input before a later promotion", () => {
+    const reducer = createV2SessionReducer()
+    reducer.reduce(
+      [],
+      event({
+        ...base,
+        id: "evt_admitted",
+        type: "session.input.admitted",
+        data: {
+          sessionID: "ses_1",
+          inputID: "msg_user",
+          input: { type: "user", delivery: "steer", data: { text: "hello" } },
+        },
+      }),
+    )
+    reducer.reduce(
+      [],
+      event({
+        ...base,
+        id: "evt_withdrawn",
+        type: "session.input.withdrawn",
+        data: { sessionID: "ses_1", inputID: "msg_user" },
+      }),
+    )
+
+    const result = reducer.reduce(
+      [],
+      event({
+        ...base,
+        id: "evt_promoted",
+        type: "session.input.promoted",
+        data: { sessionID: "ses_1", inputID: "msg_user" },
+      }),
+    )
+
+    expect(result).toMatchObject({ sessionID: "ses_1", missing: "msg_user", touched: [] })
+  })
 })

packages/app/src/context/server-session-v2-reducer.ts

@@ -29,6 +29,9 @@ export function createV2SessionReducer() {
       case "session.input.admitted":
         pending.set(key(sessionID, event.data.inputID), event.data.input)
         return result([...source])
+      case "session.input.withdrawn":
+        pending.delete(key(sessionID, event.data.inputID))
+        return result([...source])
       case "session.input.promoted": {
         const input = pending.get(key(sessionID, event.data.inputID))
         pending.delete(key(sessionID, event.data.inputID))