feat(ci): use sha instead of tag on steps

[tobiasehlert]

This pull request updates several GitHub Actions in workflow files to use explicit commit SHAs for each action, rather than floating version tags. This change improves security and reliability by ensuring the workflows always use the intended action versions, preventing unexpected updates or breaking changes.

closes #95

[Copilot]

Pull Request Overview

This pull request enhances security and reliability by replacing floating version tags with explicit commit SHAs for all GitHub Actions across workflow files. This prevents potential supply chain attacks and ensures consistent behavior by pinning actions to specific versions.

• Replaces version tags (e.g., @v4, @v5) with commit SHAs and version comments
• Updates actions across GitHub Pages, code generation, and CodeQL analysis workflows
• Maintains version information in comments for easy reference and future updates

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
.github/workflows/github-pages.yml	Updates checkout, configure-pages, upload-pages-artifact, and deploy-pages actions to use commit SHAs
.github/workflows/generate.yml	Updates checkout, setup-go, tailscale, add-and-commit, and repository-dispatch actions to use commit SHAs
.github/workflows/codeql-analysis.yml	Updates checkout, setup-go, and all CodeQL actions to use commit SHAs

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