fix: theme-aware issue on background

[timheuer]

• make toolbar window background theme-aware
• change launch settings do use devenvvar in case someone doesn't have Community installed

Description

Fixes #11 by adding the vs brush for toolwindow background

Also, I wasn't able to immediately clone and debug because of hard-coded path in launchsettings. Moved to use csproj and envvar so that anyone could use it regardless of Community, Insiders, etc. -- optional fix, but this helped me.

Type of Change

• feat - New feature
• fix - Bug fix
• docs - Documentation only
• refactor - Code change that neither fixes a bug nor adds a feature
• test - Adding or updating tests
• chore - Maintenance tasks
• ci - CI/CD changes

Related Issues

Fixes #11

Checklist

• My code follows the project's code style
• I have tested my changes locally
• I have updated documentation if needed
• My commits follow the conventional commit format
• This PR has a descriptive title using conventional commit format

Screenshots (if applicable)

Additional Notes

[CalvinAllen]

Thanks!!

🚀