fix(ai): clear conversation actually clears

useChat exposes reset() which calls setMessages(opts.initialMessages),
and the AI page passes initialLive.current as initialMessages — a ref
captured once on mount from localStorage.

resetAndClear was calling reset() then clearLive(). Sequence problem:

  reset()       → setMessages(initialLive.current)  // populated old array
  clearLive()   → localStorage.removeItem(LIVE_KEY) // does nothing to memory

The ref still held the original messages, so reset re-seeded them and
the conversation appeared to "come back" the moment you typed anything
(or sometimes immediately, depending on render timing).

Fix: blank the ref, clear localStorage, and call setMessages([])
directly. reset() is no longer needed at this call site so it's been
dropped from the useChat destructure.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/routes/ai.tsx

@@ -378,7 +378,7 @@ function ChatSurface({
   if (initialLive.current === null) {
     initialLive.current = loadLive() ?? []
   }
-  const { messages, setMessages, send, continueChat, abort, isStreaming, reset } = useChat({
+  const { messages, setMessages, send, continueChat, abort, isStreaming } = useChat({
     system: systemPrompt,
     initialMessages: initialLive.current,
   })
@@ -389,11 +389,20 @@ function ChatSurface({
     saveLive(messages)
   }, [messages])
 
-  // Wrap reset so "Clear conversation" also drops the persisted snapshot.
+  // "Clear conversation" must drop three things in lockstep:
+  //   1. The in-memory messages (setMessages([])).
+  //   2. The persisted live snapshot (clearLive()).
+  //   3. The initialLive ref — otherwise on the next render or hook
+  //      reconciliation, useChat's reset() would re-seed from the
+  //      captured-at-mount initialMessages and the old conversation
+  //      pops back. (This was the bug.)
+  // We deliberately don't call useChat's reset() here because reset
+  // restores to opts.initialMessages, which we want to be empty.
   const resetAndClear = useCallback(() => {
-    reset()
+    initialLive.current = []
     clearLive()
-  }, [reset])
+    setMessages([])
+  }, [setMessages])
 
   // Auto tool-loop using native function calls. Reads run automatically;
   // writes are held in `pendingConfirm` until the operator clicks Confirm