Replace deprecated PackageLicenseUrl and PackageIconUrl

[avgalex]

Summary

• Replaces deprecated PackageLicenseUrl with PackageLicenseExpression (MIT) — fixes License information about packages #144
• Replaces deprecated PackageIconUrl with embedded PackageIcon (NuGet 5.3+ best practice)
• Adds icon.png (128x128) to the repo root, embedded into NuGet packages

Test plan

• dotnet build succeeds without NU5048 or license warnings
• Verify .nupkg metadata contains <license type="expression">MIT</license>
• Verify .nupkg contains embedded icon.png

🤖 Generated with Claude Code

[avgalex]

@claude review this PR

[claude]

Claude finished @avgalex's task in 32s —— View job

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PR Review: Replace deprecated PackageLicenseUrl with PackageLicenseExpression

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• Review the change
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Summary

This is a minimal, focused, and correct change. The diff is clean:

- <PackageLicenseUrl>https://github.com/.../blob/master/LICENSE</PackageLicenseUrl>
+ <PackageLicenseExpression>MIT</PackageLicenseExpression>

Verdict: Approved — the change is correct and addresses the issue properly.

What's Good

• PackageLicenseExpression is the NuGet-recommended way to declare the license using an SPDX identifier (MIT). This allows license detection tools (like nuget-license) to correctly identify the license type from package metadata.
• The SPDX identifier MIT matches the repository's actual license.
• The change is minimal with no unintended side effects.

Minor Observation (non-blocking)

src/common.props:8 still uses the deprecated PackageIconUrl:

<PackageIconUrl>https://raw.githubusercontent.com/.../logo_rounded.png</PackageIconUrl>

This has been deprecated since NuGet 5.3 in favor of PackageIcon with an embedded icon file. It's not a blocker for this PR, but worth addressing in a follow-up issue.

[avgalex]

@claude review this PR

[claude]

Claude finished @avgalex's task in 1m 3s —— View job

---

PR Review: Replace deprecated PackageLicenseUrl and PackageIconUrl

• Read changed files
• Review the changes
• Post review feedback

---

Summary

This is a clean, focused PR that fully addresses the deprecation warnings. Both changes are correct and follow current NuGet best practices. Approved.

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Change 1: PackageLicenseUrl → PackageLicenseExpression

- <PackageLicenseUrl>https://github.com/.../blob/master/LICENSE</PackageLicenseUrl>
+ <PackageLicenseExpression>MIT</PackageLicenseExpression>

Correct. MIT is a valid SPDX identifier and matches the repo's actual license. This enables license detection tools (e.g. nuget-license, Dependabot) to correctly classify the package license from metadata alone, without following a URL.

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Change 2: PackageIconUrl → embedded PackageIcon

- <PackageIconUrl>https://raw.githubusercontent.com/.../logo_rounded.png</PackageIconUrl>
+ <PackageIcon>icon.png</PackageIcon>

<ItemGroup>
  <None Include="$(MSBuildThisFileDirectory)..\icon.png" Pack="true" PackagePath="" />
</ItemGroup>

Correct. The path $(MSBuildThisFileDirectory)..\icon.png correctly resolves from src/ up to the repo root where icon.png lives. PackagePath="" places the icon at the root of the .nupkg, which is what <PackageIcon>icon.png</PackageIcon> expects.

The added icon.png is a 128×128 PNG with RGBA — this matches NuGet's recommended icon dimensions.

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Minor Observations (non-blocking)

1. Old icon vs new icon: The previous PackageIconUrl pointed to a different upstream image (logo_rounded.png from the micro-elements/MicroElements repo). The new icon.png in this repo root appears to be a different asset. If visual consistency with the old branding matters, this is worth verifying — but it's a cosmetic concern, not a correctness issue.

2. PackagePath="" — an alternative convention is PackagePath="\" or PackagePath="/". Both "" and \ resolve to the package root and are functionally equivalent. Either works.

3. The <ItemGroup> with the icon <None> include is placed inside common.props, which is imported by all library .csproj files. This is the right place for it — all packages will embed the icon automatically.

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No blocking issues found. The PR is ready to merge.