Define shared content schema for writings, portfolio, bookshelf, blogs

Adds content/README.md documenting the TOML frontmatter contract each
content type must follow, plus one seed entry per type to lock the
schema in a runnable form. Bookshelf entries use a kind field ("book"
or "paper") so academic papers (DOI/arXiv id) are first-class
alongside ISBN-driven books, not bolted on later.

content/README.md

@@ -0,0 +1,98 @@
+# content/
+
+This directory is the canonical source of truth for all site content. It is
+shared between `apps/site` (Astro reads it directly at build time) and
+`apps/cms` (Strapi's custom provider reads/writes these same files — its
+SQLite database is only a disposable cache/index, never the source of
+record). The site must always be buildable straight from this directory with
+Strapi entirely absent.
+
+Frontmatter is TOML (`+++ ... +++`), matching the legacy Zola posts under
+`content/posts/` to ease migration. Each content type below is one file (or a
+directory with `index.md` for entries with co-located assets), one frontmatter
+schema.
+
+## `writings/` (blog / essays)
+
+```toml
++++
+title = "..."
+description = "..."
+author = "andwati"
+date = 2026-04-08
+updated = 2026-04-10       # optional, only when the post has been revised
+draft = false
+canonical_url = ""         # optional, only if first published elsewhere
+[taxonomies]
+tags = ["..."]
+[extra]
+series = "..."             # optional
+series_index = 1           # required if `series` is set
+llms_description = "..."   # optional per-post override of the site-wide one
++++
+```
+
+## `portfolio/` (projects / professional work)
+
+```toml
++++
+title = "..."
+description = "..."
+role = "..."
+date_start = 2025-01-01
+date_end = 2025-06-01      # optional, omit if ongoing
+outcome = "one-line result"
+draft = false
+[[links]]
+label = "Live"
+url = "https://..."
+[[links]]
+label = "Source"
+url = "https://..."
+[taxonomies]
+tags = ["..."]             # stack / tech tags
++++
+```
+
+Body is a free-form Markdown case study.
+
+## `bookshelf/` (books *and* papers)
+
+`kind` selects which identifier fields apply — books use `isbn`, papers use
+`doi`/`arxiv_id`. Cover images are fetched by a lookup (Open Library/Google
+Books for ISBNs; Semantic Scholar/arXiv for papers) and cached under
+`static/covers/`, never fetched at page-render time.
+
+```toml
++++
+title = "..."
+kind = "book"               # "book" | "paper"
+authors = ["..."]
+isbn = "9780000000000"      # books only
+doi = "10.1000/xyz123"      # papers only
+arxiv_id = "2101.00001"     # papers only, optional
+url = "https://..."         # papers only: landing page / source link
+cover_image = "/covers/slug.jpg"
+rating = 5                  # optional, 1-5
+status = "read"             # "reading" | "read" | "abandoned"
+date_started = 2026-01-01
+date_finished = 2026-01-20  # optional, omit if still in progress
+[taxonomies]
+tags = ["..."]              # genre / topic
++++
+```
+
+Body is a free-form personal review/notes.
+
+## `blogs/` (curated external blogs)
+
+```toml
++++
+title = "..."     # the blog/site's name
+url = "https://..."
+feed_url = "https://.../rss.xml"
++++
+```
+
+Body is a one-to-two sentence blurb on why you follow it. No live feed
+fetching — this list is hand-curated and static.

content/blogs/example-blog.md

@@ -0,0 +1,7 @@
++++
+title = "Example Blog"
+url = "https://example.com"
+feed_url = "https://example.com/rss.xml"
++++
+
+Placeholder blurb establishing the `blogs` content schema.

content/bookshelf/attention-is-all-you-need.md

@@ -0,0 +1,17 @@
++++
+title = "Attention Is All You Need"
+kind = "paper"
+authors = ["Ashish Vaswani", "Noam Shazeer", "Niki Parmar"]
+doi = "10.48550/arXiv.1706.03762"
+arxiv_id = "1706.03762"
+url = "https://arxiv.org/abs/1706.03762"
+cover_image = "/covers/attention-is-all-you-need.jpg"
+rating = 5
+status = "read"
+date_started = 2026-02-01
+date_finished = 2026-02-03
+[taxonomies]
+tags = ["machine-learning", "papers"]
++++
+
+Placeholder review establishing the `bookshelf` schema for `kind = "paper"`.

content/bookshelf/structure-and-interpretation-of-computer-programs.md

@@ -0,0 +1,15 @@
++++
+title = "Structure and Interpretation of Computer Programs"
+kind = "book"
+authors = ["Harold Abelson", "Gerald Jay Sussman"]
+isbn = "9780262510875"
+cover_image = "/covers/structure-and-interpretation-of-computer-programs.jpg"
+rating = 5
+status = "read"
+date_started = 2026-01-01
+date_finished = 2026-01-20
+[taxonomies]
+tags = ["computer-science", "programming"]
++++
+
+Placeholder review establishing the `bookshelf` schema for `kind = "book"`.

content/portfolio/example-project.md

@@ -0,0 +1,15 @@
++++
+title = "Example Project"
+description = "Placeholder portfolio entry establishing the schema."
+role = "Author"
+date_start = 2026-01-01
+outcome = "Established the portfolio content schema."
+draft = true
+[[links]]
+label = "Source"
+url = "https://github.com/andwati"
+[taxonomies]
+tags = ["placeholder"]
++++
+
+Placeholder case study body establishing the `portfolio` content schema.

content/writings/example-first-post/index.md

@@ -0,0 +1,15 @@
++++
+title = "Why This Site Exists"
+description = "A short note on what this new site is, and why it's more than a tech blog."
+author = "andwati"
+date = 2026-08-30
+draft = true
+[taxonomies]
+tags = ["meta"]
+[extra]
+llms_description = "An introductory post explaining the purpose of this personal digital-legacy site."
++++
+
+This is a placeholder post establishing the `writings` content schema. It will
+be replaced once the design system and migration from the old Zola posts are
+ready.