Resolve module-scope conflict; adopt agent onboarding files in docs repo

Clarify Repository-Defaults scope so agent onboarding files and repository self-sufficiency apply to every PSModule repository, while the module file set and layout stay type-specific. This removes the contradiction with the 'every repository' / 'stand on its own' requirements that had excluded PSModule/docs.

Dogfood the standard: add AGENTS.md, CLAUDE.md (@AGENTS.md import), and .github/copilot-instructions.md to PSModule/docs, which previously carried none of the required agent onboarding files.

Author: MariusStorhaug

.github/copilot-instructions.md

@@ -0,0 +1 @@
+Follow the instructions in [AGENTS.md](../AGENTS.md).

AGENTS.md

@@ -0,0 +1,19 @@
+# Agents
+
+This repository holds the source for the [PSModule](https://psmodule.io) documentation, published at [psmodule.io/docs](https://psmodule.io/docs). Everything an agent needs to work here is documentation — read it the same way a new contributor would.
+
+## Start here
+
+1. Read this file, then the [README](README.md) for what this repository is and how it builds.
+2. Read the [PSModule documentation](https://psmodule.io/docs) for the framework's why, how, and what — its standards, conventions, and style guides. The source for those pages lives under `src/docs/` in this repository.
+3. Read the [MSX documentation](https://msxorg.github.io/docs) for the organization-level principles and ways of working that sit above any single repository.
+
+## Working in this repository
+
+- Documentation pages live under `src/docs/`; the published site navigation is defined in `src/zensical.toml`. Add a new page to both.
+- The PowerShell standards and style guides under `src/docs/` are the source of truth for content changes — follow the page you are changing.
+- Keep each page the single source of truth: link to the canonical page instead of restating its content elsewhere.
+
+## The rule
+
+This file points; it never defines. Standards and process live in the documentation and are referenced by their canonical location — never copied here.

CLAUDE.md

@@ -0,0 +1 @@
+@AGENTS.md

src/docs/PowerShell/Modules/Repository-Defaults.md

@@ -15,6 +15,8 @@ They do not apply directly to:
 - Template repositories other than `Template-PSModule`.
 - Test, archive, service, or infrastructure repositories that are not published as module artifacts.
 
+Two baseline expectations still apply to every PSModule repository, including the types listed above. Each repository stands on its own — it carries its own governance and community files instead of relying on the organization `.github` fallback — and each repository ships the [agent onboarding files](#agent-onboarding-files) so an agent can work in it without prior context. What differs by type is the concrete file set and layout: the required files, README shape, and framework wiring on the rest of this page are module defaults, and non-module repositories keep only the equivalent baseline appropriate to their own type. This repository, `PSModule/docs`, follows those two baseline expectations itself.
+
 Each initiative should keep its own repository standards in its central documentation repository. For the PSModule organization, this repository is the source of truth.
 
 ## Repository creation