feat: Improve the initial setup experience

- Issue a single-use token for initial account creation
- Disable registration through other methods until the first account is made
- Print helpful instructions to the console on the first run
- Improve the welcome message sent in the admin room on first run

src/service/users/mod.rs

@@ -30,7 +30,7 @@ use ruma::{
 use serde::{Deserialize, Serialize};
 use serde_json::json;
 
-use crate::{Dep, account_data, admin, appservice, globals, rooms};
+use crate::{Dep, account_data, admin, appservice, firstrun, globals, rooms};
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct UserSuspension {
@@ -55,6 +55,7 @@ struct Services {
 	globals: Dep<globals::Service>,
 	state_accessor: Dep<rooms::state_accessor::Service>,
 	state_cache: Dep<rooms::state_cache::Service>,
+	firstrun: Dep<firstrun::Service>,
 }
 
 struct Data {
@@ -96,6 +97,7 @@ impl crate::Service for Service {
 				state_accessor: args
 					.depend::<rooms::state_accessor::Service>("rooms::state_accessor"),
 				state_cache: args.depend::<rooms::state_cache::Service>("rooms::state_cache"),
+				firstrun: args.depend::<firstrun::Service>("firstrun"),
 			},
 			db: Data {
 				keychangeid_userid: args.db["keychangeid_userid"].clone(),
@@ -187,7 +189,9 @@ impl Service {
 		self.db
 			.userid_origin
 			.insert(user_id, origin.unwrap_or("password"));
-		self.set_password(user_id, password).await
+		self.set_password(user_id, password).await?;
+
+		Ok(())
 	}
 
 	/// Deactivate account