refactor: rename content types to semantic taxonomy

- vault → notes (PKM-exported content)
- posts → articles (short-form, no TOC)
- papers → essays (long-form, with TOC)
- type: post → type: article (posts are just short articles)
- layouts/paper → layouts/essay
- 08a-paper.css → 08a-essay.css
- CSS: fix redundant li resets, remove role="main" from article,
  replace <small> prev/next labels, add console layout
- Update hugo.toml menus, internal URLs, front matter throughout
- Add docs/context.md, docs/css-refactor-plan.md

content/posts/getting-started.md

@@ -1,51 +0,0 @@
----
-title: "Getting Started with ASW-Hugo"
-description: "How to set up the ASW-Hugo pack in your Hugo project."
-date: 2026-04-08
-tags: [setup, hugo, asw]
-ai-disclosure: "generated"
-ai-model: "claude-sonnet-4-5"
-ai-provider: "Anthropic"
-
----
-
-# Getting Started with ASW-Hugo
-
-The ASW-Hugo pack is a theme that outputs [Agentic Semantic Web](https://asw.trentuna.com/) semantic HTML from your Hugo Markdown content.
-
-## Installation
-
-1. Copy or symlink `packs/hugo/` from the ASW repo:
-   ```bash
-   ln -s /path/to/agentic-semantic-web/packs/hugo/ themes/asw-hugo
-   ```
-
-2. Set `theme = "asw-hugo"` in your `hugo.toml`.
-
-3. Add tag taxonomy:
-   ```toml
-   [taxonomies]
-     tag = "tags"
-   ```
-
-4. Wire ASW CSS:
-   ```bash
-   cp /path/to/agentic-semantic-web/agentic.css \
-      themes/asw-hugo/static/css/asw.css
-   ```
-
-5. Build:
-   ```bash
-   hugo
-   ```
-
-## What you get
-
-- Semantic HTML output: `<article>`, `<section data-layout="grid">`, `<aside data-callout>`
-- Tag navigation at `/tags/`
-- Callout blocks: `{{</* callout note */>}} ... {{</* /callout */>}}`
-- Wikilinks: `{{</* wikilink "Text" "/path/" */>}}`
-
-{{< callout tip >}}
-The ASW-Hugo pack uses **system font stacks** by default — no external font loading required.
-{{< /callout >}}