[ump45nose]

What's Changed

dotnet nuget push warns that our packages have no readme. This adds a short package readme (src/README.md) and wires it up in the shared NuGet properties in Directory.Build.props (PackageReadmeFile plus a packed Content item next to the license and icon), so every packable project under src/ gets it.

The root README.md is aimed at people building the repo (build steps, relative links to source folders), so I wrote a separate, smaller one for nuget.org: what Apache Arrow is, the list of packages, a short IPC reading example and links to the docs and the repository. All links are absolute so they work on nuget.org. It carries the usual ASF license header like the other Markdown files.

Checked with dotnet pack -c Release for each project in src/: all seven .nupkg files now contain README.md at the package root and their nuspec has <readme>README.md</readme>, with no new pack warnings.

This PR was prepared with AI assistance and reviewed by me.

Closes #45.

[adamreeve]

Thanks for addressing this @ump45nose

[adamreeve]

Can you please add a short description of what this example does. Eg. "Example of reading an Arrow IPC file".

Also, this example only reads the first batch of data from the file. It could mislead people if they copy this code, thinking it will read a whole file. Maybe it should return a List<RecordBatch> instead?