Add #![no_std] and fix the fallout

src/blob.rs

@@ -5,6 +5,8 @@ use core::fmt;
 use core::sync::atomic::{AtomicU64, Ordering};
 extern crate alloc;
 use alloc::sync::{Arc, Weak};
+use alloc::boxed::Box;
+use alloc::vec::Vec;
 
 /// Shared data with an associated unique identifier.
 pub struct Blob<T> {

src/lib.rs

@@ -1,3 +1,4 @@
+#![no_std]
 // Copyright 2022 The peniko authors.
 // SPDX-License-Identifier: Apache-2.0 OR MIT