feat(api-server): add yParity for non-legacy txs (matter-labs#3246)

## What ❔

Closes matter-labs#3245

## Why ❔

See matter-labs#3245 for more details. TLDR better compatibility with ETH spec.

## Checklist

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- [x] PR title corresponds to the body of PR (we generate changelog
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- [ ] Tests for the changes have been added / updated.
- [x] Documentation comments have been added / updated.
- [x] Code has been formatted via `zkstack dev fmt` and `zkstack dev
lint`.

core/lib/dal/src/models/storage_transaction.rs

@@ -541,6 +541,13 @@ impl StorageApiTransaction {
                 .or_else(|| self.max_fee_per_gas.clone())
                 .unwrap_or_else(BigDecimal::zero),
         };
+        // Legacy transactions are not supposed to have `yParity` and are reliant on `v` instead.
+        // Other transactions are required to have `yParity` which replaces the deprecated `v` value
+        // (still included for backwards compatibility).
+        let y_parity = match self.tx_format {
+            None | Some(0) => None,
+            _ => signature.as_ref().map(|s| U64::from(s.v())),
+        };
         let mut tx = api::Transaction {
             hash: H256::from_slice(&self.tx_hash),
             nonce: U256::from(self.nonce.unwrap_or(0) as u64),
@@ -553,6 +560,7 @@ impl StorageApiTransaction {
             gas_price: Some(bigdecimal_to_u256(gas_price)),
             gas: bigdecimal_to_u256(self.gas_limit.unwrap_or_else(BigDecimal::zero)),
             input: serde_json::from_value(self.calldata).expect("incorrect calldata in Postgres"),
+            y_parity,
             v: signature.as_ref().map(|s| U64::from(s.v())),
             r: signature.as_ref().map(|s| U256::from(s.r())),
             s: signature.as_ref().map(|s| U256::from(s.s())),

core/lib/types/src/api/mod.rs

@@ -515,6 +515,9 @@ pub struct Transaction {
     pub gas: U256,
     /// Input data
     pub input: Bytes,
+    /// The parity (0 for even, 1 for odd) of the y-value of the secp256k1 signature
+    #[serde(rename = "yParity", default, skip_serializing_if = "Option::is_none")]
+    pub y_parity: Option<U64>,
     /// ECDSA recovery id
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub v: Option<U64>,

core/lib/types/src/l2/mod.rs

@@ -396,6 +396,13 @@ impl From<L2Tx> for api::Transaction {
             } else {
                 (None, None, None)
             };
+        // Legacy transactions are not supposed to have `yParity` and are reliant on `v` instead.
+        // Other transactions are required to have `yParity` which replaces the deprecated `v` value
+        // (still included for backwards compatibility).
+        let y_parity = match tx.common_data.transaction_type {
+            TransactionType::LegacyTransaction => None,
+            _ => v,
+        };
 
         Self {
             hash: tx.hash(),
@@ -409,6 +416,7 @@ impl From<L2Tx> for api::Transaction {
             max_fee_per_gas: Some(tx.common_data.fee.max_fee_per_gas),
             gas: tx.common_data.fee.gas_limit,
             input: Bytes(tx.execute.calldata),
+            y_parity,
             v,
             r,
             s,