impl Deserialize for Packed + SumTag (#4653)

# Description of Changes

See tin.

Extracted from #4311.

# API and ABI breaking changes

None

# Expected complexity level and risk

1

# Testing

Trivial additions.

Author: Centril

crates/sats/src/algebraic_value.rs

@@ -1,7 +1,7 @@
 pub mod de;
 pub mod ser;
 
-use crate::{AlgebraicType, ArrayValue, ProductValue, SumValue};
+use crate::{impl_deserialize, AlgebraicType, ArrayValue, Deserialize, ProductValue, SumValue};
 use core::mem;
 use core::ops::{Bound, RangeBounds};
 use derive_more::From;
@@ -117,6 +117,8 @@ pub enum AlgebraicValue {
 #[repr(Rust, packed)]
 pub struct Packed<T>(pub T);
 
+impl_deserialize!([T: Deserialize<'de>] Packed<T>, de => <_>::deserialize(de).map(Packed));
+
 impl<T> From<T> for Packed<T> {
     fn from(value: T) -> Self {
         Self(value)

crates/sats/src/sum_value.rs

@@ -1,4 +1,5 @@
 use crate::algebraic_value::AlgebraicValue;
+use crate::impl_deserialize;
 use crate::sum_type::SumType;
 
 /// A value of a sum type choosing a specific variant of the type.
@@ -34,6 +35,8 @@ impl SumValue {
 #[repr(transparent)]
 pub struct SumTag(pub u8);
 
+impl_deserialize!([] SumTag, de => <_>::deserialize(de).map(SumTag));
+
 #[cfg(feature = "memory-usage")]
 impl spacetimedb_memory_usage::MemoryUsage for SumTag {}