all: split reusable components into workspace crates

src/utils/once.rs

@@ -1,26 +0,0 @@
-#![allow(dead_code)]
-
-use std::{cell::Cell, future::Future};
-
-#[derive(Default)]
-pub struct Once {
-    done: Cell<bool>,
-}
-
-impl Once {
-    pub fn set(&self) -> bool {
-        !self.done.replace(true)
-    }
-
-    pub fn exec<F: FnOnce()>(&self, f: F) {
-        if !self.done.replace(true) {
-            f();
-        }
-    }
-
-    pub async fn exec_async<G: Future<Output = ()>, F: FnOnce() -> G>(&self, f: F) {
-        if !self.done.replace(true) {
-            f().await;
-        }
-    }
-}