cui cannot drive file-based apps, and dotnet cui is not the installed command #4

Context

I built a single-file dashboard with #:package CuiSharp@0.3.1, dotnet run app.cs, and an adjacent global.json. The repo's best tooling cannot drive it:

> cui png shot.png
No .NET app found at "C:\...\track".

AppLocator.Resolve only understands a directory containing a *.csproj or an explicit --app dll (src/CuiSharp.Tools/AppLocator.cs), so the file-based flow — the modern .NET 10 workflow, and the one the skill's #:package line points at — is excluded from tree, png, click, etc.

Separately: after dotnet tool install --global CuiSharp.Tools --version 0.3.1, only cui.exe lands on PATH. dotnet cui ... fails with "dotnet-cui does not exist", yet SKILL.md and llms.txt use dotnet cui throughout, so that is what every agent tries first.

Proposal

• In AppLocator, accept a .cs file (or a directory whose only project is a .cs file with #:package): build it with dotnet build <file> and drive the produced dll exactly like --app. Honour an adjacent global.json.
• Either ship the shim as dotnet-cui so dotnet cui resolves, or standardise docs on cui and make dotnet cui print a hint.
• While in there: native/tool diagnostics arrive as mojibake in a non-English-locale console; setting UTF-8 on the tool's stdout/stderr at startup would fix that.

Acceptance

cui png shot.png works in a directory containing only app.cs, global.json, and package references, and the documented command matches the installed one.