[StuartFerguson]

This PR clears the remaining Codacy-reported issues across MerchantFileProcessor, MerchantPos, SystemSetupTool, HealthChecksUI, and the ReplayParkedQueue script.

Highlights:

• Encapsulated MerchantMetricSnapshot fields behind methods/properties
• Extracted repeated route and metadata string literals
• Reduced parameter count in FileStatusStore::RecordAsync via a request record
• Removed stale comments and TODO markers
• Fixed the empty catch in ReplayParkedQueue cleanup
• Updated HealthChecksUI startup/Program signatures and EventStoreFunctions string reuse

Verification:

• dotnet build TransactionProcessing.MerchantFileProcessor\TransactionProcessing.MerchantFileProcessor.sln -v minimal
• dotnet build TransactionProcessing.MerchantPos\TransactionProcessing.MerchantPos.csproj -v minimal
• dotnet build TransactionProcessor.SystemSetupTool\TransactionProcessor.SystemSetupTool.csproj -v minimal
• dotnet build TransactionProcessor.HealthChecksUI\TransactionProcessor.HealthChecksUI\TransactionProcessor.HealthChecksUI.csproj -v minimal

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 0 complexity

Metric	Results
Complexity	0

View in Codacy

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