fix: cache Windows npm command shims

[elrrrrrrr]

Summary

• cache npm-generated Windows shims for utoo, ut, and utx
• retain legacy .exe entries while adding extensionless, .cmd, and .ps1 paths
• validate restored caches by executing utoo --version
• use a v2 cache key and add a Windows cache-restore CI job

Root cause

setup-utoo cached utoo.exe and ut.exe, but current Utoo packages expose JavaScript bin entries. npm generates .cmd and .ps1 shims on Windows, so a cache hit restored the package manifest without restoring an invokable command. The manifest-only validation then treated that incomplete cache as valid.

Validation

• npx tsc --noEmit
• npm run build
• Prettier check for changed source, workflow, action metadata, and docs
• cache layout assertions for Windows and Unix paths

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.