The PSModule coding style guides now live in the documentation site
under a new **Style Guides** menu section. Contributors and agents can
browse the GitHub Actions, Markdown, and PowerShell conventions directly
on the docs site instead of digging through editor instruction files in
another repository.

## New: Style Guides section in the docs

A new **Style Guides** entry appears in the top navigation, containing:

- **GitHub Actions** — workflow and composite action authoring
conventions: job/step naming, quoting, SHA pinning, minimal permissions,
OIDC and secrets handling, untrusted-input safety, trigger isolation,
runner pinning, and a zizmor security checklist.
- **Markdown** — headings, lists, code blocks, links, tables, emphasis,
whitespace, and filename conventions.
- **PowerShell** — One True Brace Style, naming, parameters, error
handling, pipeline design, performance, and Pester testing conventions.

Each guide states the rule, shows good and bad examples, and explains
how to apply it. The Markdown and PowerShell guides are migrated
verbatim from the editor instruction files that previously lived in the
`Process-PSModule` repository; the GitHub Actions guide is new and
aligns with the existing GitHub Actions Standard.

## Technical Details

- Added `src/docs/Style-Guides/` with `index.md`, `GitHub-Actions.md`,
`Markdown.md`, and `PowerShell.md`.
- Editor-specific frontmatter (`applyTo`) was replaced with docs
frontmatter (`title`/`description`).
- Registered the new `Style Guides` section in the `nav` array in
`src/zensical.toml`, placed between **GitHub Actions** and
**Solutions**.
- Companion PR: `PSModule/Process-PSModule#349` removes the now-migrated
instruction files.

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>