chore(lazer) Added Feed struct

lazer/contracts/evm/src/PythLazerLib.sol

@@ -2,29 +2,16 @@
 pragma solidity ^0.8.13;
 
 import {PythLazer} from "./PythLazer.sol";
+import {PythLazerStructs} from "./PythLazerStructs.sol";
 
 library PythLazerLib {
-    enum PriceFeedProperty {
-        Price,
-        BestBidPrice,
-        BestAskPrice,
-        PublisherCount,
-        Exponent
-    }
-
-    enum Channel {
-        Invalid,
-        RealTime,
-        FixedRate50,
-        FixedRate200
-    }
 
     function parsePayloadHeader(
         bytes calldata update
     )
         public
         pure
-        returns (uint64 timestamp, Channel channel, uint8 feedsLen, uint16 pos)
+        returns (uint64 timestamp, PythLazerStructs.Channel channel, uint8 feedsLen, uint16 pos)
     {
         uint32 FORMAT_MAGIC = 2479346549;
 
@@ -36,7 +23,7 @@ library PythLazerLib {
         }
         timestamp = uint64(bytes8(update[pos:pos + 8]));
         pos += 8;
-        channel = Channel(uint8(update[pos]));
+        channel = PythLazerStructs.Channel(uint8(update[pos]));
         pos += 1;
         feedsLen = uint8(update[pos]);
         pos += 1;
@@ -60,8 +47,8 @@ library PythLazerLib {
     function parseFeedProperty(
         bytes calldata update,
         uint16 pos
-    ) public pure returns (PriceFeedProperty property, uint16 new_pos) {
-        property = PriceFeedProperty(uint8(update[pos]));
+    ) public pure returns (PythLazerStructs.PriceFeedProperty property, uint16 new_pos) {
+        property = PythLazerStructs.PriceFeedProperty(uint8(update[pos]));
         pos += 1;
         new_pos = pos;
     }

lazer/contracts/evm/src/PythLazerStructs.sol

@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+library PythLazerStructs {
+    enum Channel {
+        Invalid,
+        RealTime,
+        FixedRate50,
+        FixedRate200
+    }
+
+    enum PriceFeedProperty {
+        Price,
+        BestBidPrice,
+        BestAskPrice,
+        PublisherCount,
+        Exponent,
+        Confidence,
+        FundingRate,
+        FundingTimestamp,
+        FundingRateInterval
+    }
+
+    struct Feed {
+        // Slot 1: 4 + 4 + 8 + 8 + 8 = 32 bytes (fully packed ✓)
+        uint32 feedId;
+        uint32 existsFlags;  // Bitmap: bit 0-31 for up to 32 properties
+        int64 price;
+        int64 bestBidPrice;
+        int64 bestAskPrice;
+        
+        // Slot 2: 8 + 8 + 8 + 8 = 32 bytes (fully packed ✓)
+        int64 confidence;
+        int64 fundingRate;
+        uint64 fundingTimestamp;
+        uint64 fundingRateInterval;
+        
+        // Slot 3: 2 + 2 = 4 bytes (28 bytes wasted, but unavoidable)
+        uint16 publisherCount;
+        int16 exponent;
+    }
+
+    struct Update {
+        uint64 timestamp;
+        Channel channel;
+        Feed[] feeds;
+    }
+
+    // Bitmap constants for Feed.existsFlags
+    uint32 constant PRICE_EXISTS = 0x01;              // bit 0
+    uint32 constant BEST_BID_EXISTS = 0x02;           // bit 1
+    uint32 constant BEST_ASK_EXISTS = 0x04;           // bit 2
+    uint32 constant PUBLISHER_COUNT_EXISTS = 0x08;    // bit 3
+    uint32 constant EXPONENT_EXISTS = 0x10;           // bit 4
+    uint32 constant CONFIDENCE_EXISTS = 0x20;         // bit 5
+    uint32 constant FUNDING_RATE_EXISTS = 0x40;       // bit 6
+    uint32 constant FUNDING_TS_EXISTS = 0x80;         // bit 7
+    uint32 constant FUNDING_INTERVAL_EXISTS = 0x100;  // bit 8
+}
+