v2: Add CI/CD workflows, analyzer settings, and repo structure

[Johnholli]

What

• Added GitHub Actions for PowerShell linting (PSScriptAnalyzer) and testing (Pester)
• Added Markdown lint workflow for docs
• Created repo structure for scripts, tests, configs
• Added CI/CD badges to README

Why

• Demonstrates automation and DevOps workflow skills
• Introduces continuous validation of PowerShell scripts
• Improves repo organization and readability
• Adds visible build signals (badges) for recruiters

How to Test

• Check Actions tab — both workflows should run automatically
• Ensure both pass with ✅
• Merge into main after success