Feat/ddraig pages (#459)

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SPDX-License-Identifier: CC-BY-SA-4.0
Copyright (c) Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
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## Summary

<!-- What does this PR do, and why? -->

Closes #

## Type of change

- [ ] 🐛 Bug fix (non-breaking change that fixes an issue)
- [ ] ✨ New feature (non-breaking change that adds functionality)
- [ ] 💥 Breaking change (would change existing behaviour)
- [ ] 🕳️ Soundness fix (fixes a checker/proof false-negative)
- [ ] 📖 Documentation
- [ ] 🧹 Refactor / tech debt (behaviour-preserving)
- [ ] ⚡ Performance
- [ ] 🔧 Build / CI / tooling

## How has this been verified?

<!-- Establish ground truth: which tool did you RUN, and what did it
report?
     Don't cite a status doc — cite the command and its output. -->

## Checklist

- [ ] My commits are **signed** (`git commit -S`).
- [ ] I ran the project's own checks/tests locally and they pass.
- [ ] New files carry the correct `SPDX-License-Identifier` (code/config
`MPL-2.0`,
      prose `CC-BY-SA-4.0`); I did not relicense existing files.
- [ ] Docs are updated, and no public claim now overstates what the code
does.
- [ ] I have not introduced a soundness hole (or I have flagged where I
might have).

## Notes for reviewers

<!-- Anything that needs special attention, follow-up, or context. -->

----
## Summary by Gitar

- **CI / Build:**
- Added `pages.yml` workflow to build and deploy documentation via
Ddraig SSG
- **Documentation:**
- Updated licenses in `the-hotchocolabot` to `PMPL-1.0-or-later` for
code and `CC-BY-SA-4.0` for docs

<sub>This will update automatically on new commits.</sub>

---------

Co-authored-by: Mistral Vibe <vibe@mistral.ai>

Author: hyperpolymath

bots/the-hotchocolabot/LICENSE

@@ -1,4 +1,11 @@
-SPDX-License-Identifier: MPL-2.0
+Code is licensed under Palimpsest Public License Version 1.0 (PMPL-1.0-or-later).
+Documentation is licensed under Creative Commons Attribution-ShareAlike 4.0 International (CC-BY-SA-4.0).
+
+See LICENSES/ directory for full license texts.
+
+---
+
+SPDX-License-Identifier: PMPL-1.0-or-later
 SPDX-FileCopyrightText: 2024-2025 Palimpsest Stewardship Council
 
 ================================================================================