Complete NuGet package metadata #93

NuGet package metadata for this repository's packages is incomplete or inconsistent (for example author, project URL pointing at source instead of docs, missing tags, missing packed icon/README, or test projects that are packable). Fix the MSBuild package properties so the next release publishes complete metadata: Authors=Cratis, PackageProjectUrl to the product docs on https://www.cratis.io/, tags, license, packed README and icon, and IsPackable=false on test/fixture projects.

Unlisting or deprecating already published test or legacy package versions is an owner decision and not part of this issue.

Part of Cratis/SEO#11.

Status

State: Done — Released in v0.26.1 via PR #94
Branch: workflows-173-dedupe-package-prs (#94)
Scope: NuGet metadata, branch seo/package-metadata
Plan: True-merge PR94's metadata-only branch into the verified Specifications 5 candidate, preserving history. Rerun affected Release build, package metadata/API validation and clean consumer checks; retain unchanged behavioral evidence explicitly.
Delivered: Nothing yet.
Remaining: To be confirmed.
Follow-ups: None.