## Summary

Added comprehensive documentation to all scripts across the repository. No functional code was modified — only documentation was added or improved.

### Changes by file

- **`bin/checkScripts/downloadCert.js`**: Added JSDoc block for `downloadCert()` with `@async`, `@param`, `@returns`, and `@example` tags. Fixed missing newline at end of file.

- **`bin/checkScripts/runDownloadCert.js`**: Added JSDoc blocks for the `OUTPUT_FILE` constant and the IIFE entry point. Fixed missing newline at end of file.

- **`cleanup-old-workflows.ps1`**: Added `.SYNOPSIS`, `.DESCRIPTION`, `.EXAMPLE`, and `.NOTES` comment-based help block.

- **`create-download-cert.ps1`**: Added full comment-based help describing both generated workflow files (`download-cert.yml` and `powershell-ci.yml`).

- **`create-powershell-ci.ps1`**: Added comment-based help detailing the multi-OS CI pipeline it generates.

- **`run-workflow-manually.ps1`**: Added comment-based help documenting the GitHub REST API usage, authentication requirements, and interactive prompts.

- **`scripts/fetch-profile.ps1`**: Added comment-based help with `.PARAMETER Username` and two `.EXAMPLE` entries. Fixed leading BOM character. Fixed missing newline at end of file.

- **`scripts/init.ps1`**: Added comment-based help with startup banner description and example output. Fixed leading BOM character. Fixed missing newline at end of file.

- **`scripts/ui_improvements.py`**: Added module-level docstring describing the headless Chrome automation workflow, dependencies, and usage notes. Added inline comments for key steps.

- **`start-automation.ps1`**: Added top-level comment-based help describing the two orchestrated components (webhook listener + ngrok). Added inline `.SYNOPSIS`/`.DESCRIPTION` doc blocks for `Start-Listener` and `Start-Ngrok` helper functions.

- **`tests/Project.Tests.ps1`**: Added comment-based help summarising both `Describe` blocks. Fixed leading BOM character.

- **`webhooks/listener.ps1`**: Added detailed comment-based help covering the request-handling loop, GitHub detection logic, and early-response optimisation rationale. Fixed leading BOM character. Fixed missing newline at end of file.