fix(sdk,webapp): drop stale lastOutTimestamp from snapshot test fixtures

vitest was happy with the extra property at runtime so the local suite
passed, but tsc on the typecheck job (strict on object literals) caught
three test fixtures still setting the field after it was removed from
ChatSnapshotV1 in the resume-cursor commit.

Author: ericallam

apps/webapp/test/chat-snapshot-integration.test.ts

@@ -49,7 +49,6 @@ function makeSnapshot(opts: { messages?: UIMessage[]; lastOutEventId?: string }
       },
     ],
     lastOutEventId: opts.lastOutEventId ?? "evt-42",
-    lastOutTimestamp: 1_700_000_000_500,
   };
 }
 

apps/webapp/test/replay-after-crash.test.ts

@@ -267,7 +267,6 @@ describe("replay after crash (MinIO + SDK helpers)", () => {
           { id: "a-1", role: "assistant", parts: [{ type: "text", text: "stale-assistant" }] },
         ],
         lastOutEventId: "evt-prev",
-        lastOutTimestamp: 1_700_000_000_500,
       };
 
       // Use the SDK's own writer to lay the snapshot down, then swap

packages/trigger-sdk/test/chat-snapshot.test.ts

@@ -29,7 +29,6 @@ function buildSnapshot(count = 1): ChatSnapshotV1 {
       parts: [{ type: "text" as const, text: `hello ${i}` }],
     })),
     lastOutEventId: "evt-42",
-    lastOutTimestamp: 2_000_000,
   };
 }