Issue Description

The repository needs PowerShell scripts for linting and validation tasks, including PSScriptAnalyzer, markdown link checking, and frontmatter validation, plus a shared helper module.

Additional Context

Files to add:

• scripts/linting/Invoke-PSScriptAnalyzer.ps1 - PowerShell code analysis
• scripts/linting/Invoke-LinkLanguageCheck.ps1 - Combined link and language checking
• scripts/linting/Link-Lang-Check.ps1 - Link validation wrapper
• scripts/linting/Markdown-Link-Check.ps1 - Markdown link checking
• scripts/linting/Validate-MarkdownFrontmatter.ps1 - YAML frontmatter validation
• scripts/linting/Modules/LintingHelpers.psm1 - Shared helper functions
• scripts/linting/README.md - Linting scripts documentation

Priority: Wave 2 (Priority 2) - Depends on Wave 1 completion

Dependencies: Requires scripts/README.md from Issue #2, PSScriptAnalyzer.psd1 and markdown-link-check.config.json from Issue #3

Testing: Execute each script with sample files, verify JSON output format, test helper module import