Technically OP should have prefixed with "Show HN:" which is what it is perhaps.
Not all "Show HN:" posts exhibit brilliance or originality or solve a problem or as in this case solve a problem for the OP for which there is already an outstanding solution (I guess originality), but the existing solution doesn't fit their use-case.
And you know as hackers (I still am at 48 yrs old) if there's an itch needing to be scratched why not show off a bit of code, it's one of the best things about HN, we learn so much from each other this way, either through (constructive) criticism or just looking at a nice bunch of code.
Searching Caddy's Github repo, 0 hits on 'livereload'. I usually do the python or ruby one-liner when I need a quick webserver, but if devd does dead simple LiveReload I might start using it just for that.
[0] https://caddyserver.com/