perf(webui): accelerate JSONL session list and thread loading (#5194)

webui/src/hooks/useSessions.ts

@@ -20,7 +20,7 @@ import type {
 } from "@/lib/types";
 
 const EMPTY_MESSAGES: UIMessage[] = [];
-const INITIAL_HISTORY_PAGE_LIMIT = 160;
+const INITIAL_HISTORY_PAGE_LIMIT = 80;
 const OLDER_HISTORY_PAGE_LIMIT = 120;
 const CHAT_CREATE_TIMEOUT_MS = 60_000;
 

webui/src/tests/useSessions.test.tsx

@@ -685,7 +685,7 @@ describe("useSessions", () => {
       "tok",
       "websocket:paged",
       expect.objectContaining({
-        limit: 160,
+        limit: 80,
         direction: "latest",
         signal: expect.any(AbortSignal),
       }),