Membership refactor

Introduce deactivate, membership services

Move membership and user deactivation functions from api crate into those services

src/service/membership/kick.rs

@@ -0,0 +1,63 @@
+use ruma::{
+	RoomId, UserId,
+	events::room::member::{MembershipState, RoomMemberEventContent},
+};
+use tuwunel_core::{Err, Result, implement, pdu::PduBuilder};
+
+use super::Service;
+use crate::rooms::timeline::RoomMutexGuard;
+
+#[implement(Service)]
+#[tracing::instrument(
+    level = "debug",
+    skip_all,
+    fields(%sender_user, %room_id, %user_id)
+)]
+pub async fn kick(
+	&self,
+	room_id: &RoomId,
+	user_id: &UserId,
+	reason: Option<&String>,
+	sender_user: &UserId,
+	state_lock: &RoomMutexGuard,
+) -> Result {
+	// kicking doesn't make sense if there is no membership
+	let Ok(event) = self
+		.services
+		.state_accessor
+		.get_member(room_id, user_id)
+		.await
+	else {
+		return Ok(());
+	};
+
+	// this is required to prevent ban -> leave transitions
+	if !matches!(
+		event.membership,
+		MembershipState::Invite | MembershipState::Knock | MembershipState::Join,
+	) {
+		return Err!(Request(Forbidden(
+			"Cannot kick a user who is not apart of the room (current membership: {})",
+			event.membership
+		)));
+	}
+
+	self.services
+		.timeline
+		.build_and_append_pdu(
+			PduBuilder::state(user_id.to_string(), &RoomMemberEventContent {
+				membership: MembershipState::Leave,
+				reason: reason.cloned(),
+				is_direct: None,
+				join_authorized_via_users_server: None,
+				third_party_invite: None,
+				..event
+			}),
+			sender_user,
+			room_id,
+			state_lock,
+		)
+		.await?;
+
+	Ok(())
+}