Async Prompt

Runs prompt functions in separate processes to prevent blocking, ensuring shell responsiveness even with slow computations like Git status checks, as demonstrated in the key features and demo.

Allows setting custom indicators like '…' or grayed-out previous prompts via functions like `fish_prompt_loading_indicator`, with detailed examples and images in the README.

Supports asynchronizing any function called from the prompt through the `async_prompt_functions` variable, enabling granular control over what runs in the background.

Permits changing the internal signal from default SIGUSR1 to SIGUSR2 via configuration, helping avoid conflicts with other plugins or programs.