This way we can improve unload-certificate prompt. While here, move the cert handling in make_request().

While here replace GEMINI_URL_LEN with TOFU_URL_MAX_LEN to avoid a dependency on telescope.h. Ideally, we should move this stuff to another header that comes with less dependencies.

try to not include headers from headers, and remove some redundant include. This helps in modularizing the codebase and also helps during incremental compilations.

don't do it in telescope.h, remove telescope.h from gencmd.awk and sort the headers in parse.y while here.

avoid the word "use" since it's better to show first use-certificate instead of this niche function.