Cross-runtime consistency fixes

[sliedig]

Summary

A set of fixes to align the .NET runtime with the other runtimes (Java, Python, TypeScript) for functional equivalence and cross-runtime consistency.

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Contracts Service

Metric name correction (ContractEventHandler.cs)

• CreateContractAsync: renamed metric from "NewContracts" to "ContractCreated"
• Aligns with the canonical metric name used by all other runtimes

Missing metric (ContractEventHandler.cs)

• UpdateContractAsync: added Metrics.AddMetric("ContractUpdated", 1, MetricUnit.Count, MetricResolution.Standard) after a successful UpdateItemAsync call
• The update path previously emitted no custom metric; this brings it in line with all other runtimes