rust: remove async-recursion dep

Since Rust
1.77 (https://github.com/rust-lang/rust/blob/ba956ef4b00c91579cff9b2220358ee3a46d982f/RELEASES.md#version-1770-2024-03-21),
async recursion is suppoerted out of the box. The example in
rust-lang/rust#117703 shows how to use
`Box::pin()` to avoid this error message:

```
note: a recursive `async fn` call must introduce indirection such as
`Box::pin` to avoid an infinitely sized future
```

This commit reduces the binary size by 1656 bytes.

Author: benma

src/rust/Cargo.lock

@@ -44,7 +44,6 @@ minicbor = { version = "0.20.0", default-features = false, features = ["alloc"],
 crc = { version = "3.0.1", optional = true }
 ed25519-dalek = { version = "2.0.0", default-features = false, features = ["hazmat"], optional = true }
 lazy_static = { version = "1.4.0", optional = true }
-async-recursion = "1.0.5"
 hmac = { version = "0.12.1", default-features = false, features = ["reset"] }
 
 miniscript = { version = "11.0.0", default-features = false, features = ["no-std"], optional = true }

src/rust/bitbox02-rust/Cargo.toml

@@ -288,25 +288,25 @@ async fn encode_member<U: sha3::digest::Update>(
     title_suffix: Option<String>,
 ) -> Result<(), Error> {
     if member_type.r#type == DataType::Struct as _ {
-        let value_encoded = hash_struct(
+        let value_encoded = Box::pin(hash_struct(
             types,
             root_object,
             &member_type.struct_name,
             path,
             formatted_path,
             title_suffix,
-        )
+        ))
         .await?;
         hasher.update(&value_encoded);
     } else if member_type.r#type == DataType::Array as _ {
-        let encoded_value = hash_array(
+        let encoded_value = Box::pin(hash_array(
             types,
             member_type,
             root_object,
             path,
             formatted_path,
             title_suffix,
-        )
+        ))
         .await?;
         hasher.update(&encoded_value);
     } else {
@@ -341,7 +341,6 @@ async fn encode_member<U: sha3::digest::Update>(
     Ok(())
 }
 
-#[async_recursion::async_recursion(?Send)]
 async fn hash_array(
     types: &[StructType],
     member_type: &MemberType,
@@ -404,7 +403,6 @@ async fn hash_array(
     Ok(hasher.finalize().to_vec())
 }
 
-#[async_recursion::async_recursion(?Send)]
 async fn hash_struct(
     types: &[StructType],
     root_object: RootObject,