[Bug]: MigrationMetrics records version span only on success, not failure

[Splatcrafter]

AI REVIEWED

Module: spring-boot-starter
File: spring/metrics/MigrationMetrics.java (~line 270)
Severity: Medium

Summary

recordSuccess() records the version span metric, but recordFailure() does not. This creates inconsistent metrics — you can't correlate failure rates with migration span size.

Suggested Fix

Record version span in both success and failure paths:

public void recordFailure(String domain, int fromVersion, int toVersion, Throwable error) {
    final int span = Math.abs(toVersion - fromVersion);
    getOrCreateVersionSpan(domain).record(span);
    getOrCreateFailureCounter(domain, classifyError(error)).increment();
}