Slow chat startup: npx commands for mcp, @upsta, and @model block chat initiation #820

There is a noticeable delay when starting a chat session in opencode. When a user opens opencode and writes in the chat (e.g., "hi"), there is a delay before a response appears. This appears to be due to the application executing npx commands for multiple processes—such as loading the mcp servers, as well as @upsta and @model—right when a chat session is initiated, which may hold up the main thread and block chat responsiveness.

Questions to consider:

• Does loading the mcp servers need to hold the main thread, or could it be deferred or parallelized?
• Can the startup of @upsta and @model (also using npx) be optimized so chat is available more quickly?

Steps to reproduce:

1. Open opencode.
2. Write "hi" in the chat.
3. Notice the delay before receiving a response.

Expected behavior:j Chat should respond with minimal delay. Startup times should be improved by optimizing how and when npx is run for mcp, @upsta, and @model, and by exploring whether mcp loading can avoid holding the main thread.