feat: Generate admin command documentation

The first part of getting admin command docs on the website.

There's also the beginnings of manpage generation here, although it's
kinda sus and I'm not sure how it's supposed to work. I'll leave that to
anyone who wants to package it.

We introduce the beginings of the xtask pattern here - we do a lot of
file generation, I thought it would be best to avoid doing that on every
compilation. It also helps avoid lots of runtime deps.

We'll need to document generating this stuff & probably add pre-commit
hooks for it, though.

src/admin/debug/mod.rs

@@ -11,7 +11,7 @@ use crate::admin_command_dispatch;
 
 #[admin_command_dispatch]
 #[derive(Debug, Subcommand)]
-pub(super) enum DebugCommand {
+pub enum DebugCommand {
 	/// - Echo input of admin command
 	Echo {
 		message: Vec<String>,

src/admin/debug/tester.rs

@@ -4,7 +4,7 @@ use crate::{admin_command, admin_command_dispatch};
 
 #[admin_command_dispatch]
 #[derive(Debug, clap::Subcommand)]
-pub(crate) enum TesterCommand {
+pub enum TesterCommand {
 	Panic,
 	Failure,
 	Tester,