Improve numeric conversions in Balancer V2 fixed point math

- Replace lossy unwrap_or fallbacks with direct unwrap() in Bfp Debug impl
- Fix to_f64_lossy() to use string parsing for accurate large value conversion
- Update test helper functions to use string-based U256/f64 conversions instead of lossy casts
- Simplify into_legacy() calls by using method syntax instead of fully qualified paths

Author: AryanGodara

crates/shared/src/sources/balancer_v2/swap/fixed_point.rs

@@ -89,17 +89,22 @@ impl FromStr for Bfp {
 impl Debug for Bfp {
     fn fmt(&self, formatter: &mut Formatter) -> fmt::Result {
         let remainder = self.0 % *ONE_18;
-        let low: u128 = remainder.try_into().unwrap_or(0);
+        let low: u128 = remainder.try_into().unwrap();
         write!(formatter, "{}.{:0>18}", self.0 / *ONE_18, low)
     }
 }
 
 impl Bfp {
     #[cfg(test)]
     pub fn to_f64_lossy(self) -> f64 {
-        // Convert U256 to f64 by taking the high bits
-        let val: u128 = self.as_uint256().try_into().unwrap_or(u128::MAX);
-        (val as f64) / 1e18
+        // NOTE: This conversion is lossy and may not be accurate for large values.
+        // It is only intended for use in tests.
+        let val: f64 = self
+            .as_uint256()
+            .to_string()
+            .parse()
+            .unwrap_or(f64::INFINITY);
+        val / 1e18
     }
 
     pub fn as_uint256(self) -> U256 {

crates/shared/src/sources/balancer_v2/swap/stable_math.rs

@@ -229,12 +229,11 @@ mod tests {
     };
 
     fn u256_from_f64_lossy(val: f64) -> U256 {
-        U256::from(val as u64)
+        U256::from_str_radix(&val.round().to_string(), 10).unwrap_or(U256::MAX)
     }
 
     fn u256_to_f64_lossy(val: U256) -> f64 {
-        let v: u128 = val.try_into().unwrap_or(u128::MAX);
-        v as f64
+        val.to_string().parse().unwrap_or(f64::INFINITY)
     }
 
     // interpreted from

crates/solvers/src/boundary/liquidity/stable.rs

@@ -2,6 +2,7 @@ pub use shared::sources::balancer_v2::pool_fetching::StablePool as Pool;
 use {
     crate::domain::{eth, liquidity},
     alloy::primitives::{Address, B256, U256},
+    ethrpc::alloy::conversions::IntoLegacy,
     shared::sources::balancer_v2::{
         pool_fetching::{AmplificationParameter, CommonPoolState, TokenState},
         swap::fixed_point::Bfp,
@@ -39,7 +40,7 @@ pub fn to_boundary_pool(address: Address, pool: &liquidity::stable::Pool) -> Opt
 
     Some(Pool {
         common: CommonPoolState {
-            id: ethrpc::alloy::conversions::IntoLegacy::into_legacy(id),
+            id: id.into_legacy(),
             address,
             swap_fee,
             paused: false,

crates/solvers/src/boundary/liquidity/weighted_product.rs

@@ -2,6 +2,7 @@ pub use shared::sources::balancer_v2::pool_fetching::WeightedPool as Pool;
 use {
     crate::domain::{eth, liquidity},
     alloy::primitives::{Address, B256, U256},
+    ethrpc::alloy::conversions::IntoLegacy,
     shared::sources::balancer_v2::{
         pool_fetching::{CommonPoolState, TokenState, WeightedPoolVersion, WeightedTokenState},
         swap::fixed_point::Bfp,
@@ -40,7 +41,7 @@ pub fn to_boundary_pool(
 
     Some(Pool {
         common: CommonPoolState {
-            id: ethrpc::alloy::conversions::IntoLegacy::into_legacy(id),
+            id: id.into_legacy(),
             address,
             swap_fee,
             paused: false,