Problem: first completion request blocked the UI with three sequential
synchronous vim.system():wait() calls (man page, command names,
command list), and every subsequent completion unnecessarily
deep-copied the entire cache.
Solution: run all three system calls concurrently via vim.system
callbacks, merging results when all complete. Queue pending completion
requests during loading. Return cached items directly instead of
deep-copying.
Barrett Ruth
ec1d9517a7
