Add optional serde support to SimHash and geo_filters crate

Author: itsibitzi

crates/geo_filters/Cargo.toml

@@ -14,6 +14,7 @@ bench = false
 
 [features]
 default = []
+serde = ["dep:serde"]
 evaluation = [
     "dep:clap",
     "dep:hyperloglogplus",
@@ -31,6 +32,7 @@ once_cell = "1.18"
 rand = { version = "0.9", optional = true }
 rayon = { version = "1.7", optional = true }
 regex = { version = "1", optional = true }
+serde = { version = "1.0", default-features = false, optional = true }
 
 [dev-dependencies]
 criterion = "0.6"

crates/geo_filters/src/diff_count/sim_hash.rs

@@ -21,6 +21,8 @@ pub type BucketId = usize;
 /// SimHash is a hash computed over a continuous range of bits from a GeoDiffCount.
 /// It is used to quickly find similar sets with a reverse index.
 #[derive(Copy, Clone, Default, Debug, Hash, PartialEq, Eq, PartialOrd, Ord)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "serde", serde(transparent))]
 pub struct SimHash(pub u64);
 
 impl SimHash {