citizen: implement Convert latest review findings into one concrete code change with a short validation note.

contracts/LabHelper.sol

@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import "./interfaces/ILabRegistry.sol";
+import "@openzeppelin/contracts/utils/math/SafeMath.sol";
+
+library LabHelper {
+    using SafeMath for uint256;
+
+    struct LabMetadata {
+        address owner;
+        uint256 createdAt;
+        uint256 lastUpdated;
+        uint256 totalContributions;
+        bool isActive;
+    }
+
+    struct ContributionRecord {
+        address contributor;
+        uint256 amount;
+        uint256 timestamp;
+        bytes32 contributionHash;
+        bool validated;
+    }
+
+    event ContributionRecorded(
+        address indexed contributor, 
+        uint256 amount, 
+        bytes32 contributionHash
+    );
+
+    function validateContribution(
+        ContributionRecord memory record, 
+        uint256 minContributionAmount
+    ) internal pure returns (bool) {
+        require(record.amount >= minContributionAmount, "Contribution below minimum threshold");
+        require(record.contributor != address(0), "Invalid contributor address");
+        require(record.contributionHash != bytes32(0), "Missing contribution hash");
+        
+        return true;
+    }
+
+    function calculateContributionScore(
+        ContributionRecord memory record, 
+        uint256 baseScore
+    ) internal view returns (uint256) {
+        uint256 timeSinceContribution = block.timestamp.sub(record.timestamp);
+        uint256 scoreMultiplier = timeSinceContribution > 30 days ? 2 : 1;
+        
+        return record.amount.mul(baseScore).mul(scoreMultiplier);
+    }
+
+    function mergeContributions(
+        ContributionRecord memory existing, 
+        ContributionRecord memory newRecord
+    ) internal pure returns (ContributionRecord memory) {
+        require(existing.contributor == newRecord.contributor, "Contributor mismatch");
+        
+        return ContributionRecord({
+            contributor: existing.contributor,
+            amount: existing.amount.add(newRecord.amount),
+            timestamp: block.timestamp,
+            contributionHash: keccak256(abi.encodePacked(existing.contributionHash, newRecord.contributionHash)),
+            validated: existing.validated && newRecord.validated
+        });
+    }
+
+    function recordContribution(
+        LabMetadata storage labMetadata, 
+        ContributionRecord memory record
+    ) internal {
+        require(validateContribution(record, 0.01 ether), "Invalid contribution");
+        
+        labMetadata.totalContributions = labMetadata.totalContributions.add(record.amount);
+        labMetadata.lastUpdated = block.timestamp;
+        
+        emit ContributionRecorded(record.contributor, record.amount, record.contributionHash);
+    }
+}