Performance optimization for long character roleplay conversations

Hi,

When roleplaying with characters over extended sessions (100+ messages), the chat becomes increasingly laggy and unresponsive. Even on high-end PCs (Ryzen 9 9900X3D, 64GB RAM, high-end GPU), the browser struggles with:

• Slow message input response

• Delayed scrolling

• General UI freeze when new messages arrive

Root cause:
The entire conversation history remains in the DOM with full rendering overhead. While content-visibility: auto helps, the DOM size still grows indefinitely, causing memory and layout calculation issues.

This makes long-form roleplay sessions frustrating to use.