String-Extensions has no PackageValidation gate

[Chris-Wolfgang]

Fleet audit (2026-07-23) found this repo does not have the fleet-standard PackageValidation gate on its published package. That leaves consumers unprotected against unintentional binary-breaking changes at the next release.

What's missing

<EnablePackageValidation>true</EnablePackageValidation> and <PackageValidationBaselineVersion>{last-published}</PackageValidationBaselineVersion> in the src csproj (or Directory.Build.props).

What to add

<PropertyGroup>
  <EnablePackageValidation>true</EnablePackageValidation>
  <PackageValidationBaselineVersion>{LAST_SHIPPED_VERSION}</PackageValidationBaselineVersion>
</PropertyGroup>

Update PackageValidationBaselineVersion on each release to the previous published version (fleet convention: keep at last-published, not vNext — see reference_packagevalidation_baseline_timing).

To waive an intentional break, add CompatibilitySuppressions.xml with the specific rule ID + target (see reference_apicompat_suppression_intentional_break).

Reference

Fleet exemplars: ETL-Abstractions#302 (PATCH via csproj, no CLI apicompat step), ETL-FixedWidth, System.Mail-Extensions.

Tracked as part of the 2026-07-23 fleet API-surface audit.