Cross-runtime consistency fixes

[sliedig]

Summary

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

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Contracts Service

DynamoDB attribute name (contractEventHandler.ts)

• updateContract: changed UpdateExpression from 'set contract_status = :t, modified_date = :m' to 'set contract_status = :t, contract_last_modified_on = :m'
• This corrects a bug where updateContract wrote to a non-existent modified_date attribute instead of the correct contract_last_modified_on attribute written by createContract

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Web Service

Event source from environment variable (requestApprovalFunction.ts)

• Replaced hardcoded 'unicorn-web' source in the firePropertyEvent call with process.env.SERVICE_NAMESPACE ?? 'unicorn-web'
• Ensures the EventBridge event Source field reflects the SERVICE_NAMESPACE environment variable, consistent with other runtimes

Metric name correction (publicationEvaluationEventHandler.ts)

• Changed metrics.addMetric('ContractUpdated', ...) to metrics.addMetric('PropertiesApproved', ...)
• ContractUpdated was incorrect for this handler (which tracks property publication evaluation, not contract updates)

Evaluation result validation (publicationEvaluationEventHandler.ts)

• Added guard to only process events where evaluationResult is 'APPROVED' or 'DECLINED'
• Logs a warning and returns without writing to DynamoDB for any other value

Structured logging in propertySearchFunction.ts

• Replaced all console.log(...) calls in the propertyDetails method with logger.info(...)
• Ensures all log output goes through the Powertools structured logger rather than raw console.log