Improve evaluate performance, throttling resilience, and add build to…

[RobinpZA]

…oling

Performance and correctness:

• Cache phishing-resistant auth-strength classification at module scope via Get-PhishingResistantStrengthId so comprehensive runs make one Graph call instead of one per scenario
• Replace O(n^2) array += accumulation in Get-CATenantUsers and Get-CAPolicy with List[object].AddRange, and trim MaxUsers in place
• Honor the server Retry-After header with a bounded retry loop on 429 so throttled evaluations are retried rather than recorded as permanent errors (new Get-RetryAfterSeconds helper, -MaxThrottleRetries parameter)
• Fix verbose paging log that fired almost every page instead of every ~1000
• Rename $pId to $policyId to avoid the readonly automatic variable

Tooling and conventions:

• Add build.ps1 (Analyze/Test/Build/CI/Clean) and PSScriptAnalyzerSettings.psd1
• Add GitHub Actions CI workflow running Analyze -> Test -> Build
• Define module-scope EvaluateUri constant for the beta endpoint
• Align manifest CompanyName with workspace convention
• Add Pester coverage for the two new helpers; document build flow in README