feat: rename to paperspec and add the website

- Rename manuspec to paperspec everywhere outside pixi.toml: prose, the
  tools, provenance tool names and the fixture key derivations, so every
  fixture and vector is rebuilt.
- Move the namespace addresses under the site, mirroring the repository:
  schema $id https://paperspec.scient.ing/schemas/<file>, the JSON-LD
  context https://paperspec.scient.ing/context/scienting-1.jsonld, and
  term IRIs https://paperspec.scient.ing/vocab#<term>. Format
  identifiers (scienting-*) and URNs (urn:scienting:) are unchanged.
- tools/site.py (standard library only) builds _site/: every file of the
  repository at its own path, each Markdown file rendered as a page with
  sidebar navigation, heading anchors matching the forge's, folder
  listings, a vocabulary page for the context's IRIs, a heading search
  and a 404 page; light and dark themes.
- check.py builds the site and checks that every Markdown file has a
  page, every internal link and fragment resolves, no Markdown is left
  unrendered, and every $id, the context address and the vocabulary IRIs
  are files of the site.
- deploy/: a Caddyfile with the media types and CORS the data needs, and
  a guide; .gitea/workflows/site.yml builds on main and publishes with
  rsync when the SITE_* secrets are set.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/concepts.md

@@ -16,8 +16,8 @@ It defines 29 formats, 18 of them `candidate` and 11 `provisional`, as [registry
 The provisional ones are the project, bundle, dataset, digitization, view, snapshot, draft-ids, exercise, submission, grade and checklist formats; the sections below say so where they describe them.
 
 Format identifiers such as `scienting-anchor/1` and `scienting-correction/1` begin with `scienting-`, which is the formats' namespace.
-The repository's name, manuspec, is a separate matter, and the formats are named after what they hold.
-The repository is at <https://git.scient.ing/infra/manuspec>.
+The repository's name, paperspec, is a separate matter, and the formats are named after what they hold.
+The repository is at <https://git.scient.ing/infra/paperspec>.
 
 ## Hashes and canonical JSON
 
@@ -89,7 +89,7 @@ Page breaks, running heads and columns are not nodes; they are geometry ([chapte
 See [chapter 3](../spec/03-nodes.md).
 
 Close relatives: [JATS 1.4](https://www.niso.org/publications/z3996-2024-jats) is an XML format in which publishers and archives exchange journal content, and TEI is a set of guidelines for encoding scholarly text.
-Each is the better choice for its own job, and the manuspec formats do not replace them; a JATS file can be one witness of a document.
+Each is the better choice for its own job, and the paperspec formats do not replace them; a JATS file can be one witness of a document.
 The element list in the [JATS 1.4 archiving tag library](https://jats.nlm.nih.gov/archiving/tag-library/1.4/) shows sections, paragraphs, table wrappers and cells and has no sentence element, while [TEI has an `<s>` element](https://tei-c.org/release/doc/tei-p5-doc/en/html/ref-s.html).
 Here the sentence is the unit that gets an ID and hashes.
 See [the comparison page](comparison.md).