Paper schema and status

Paper records have two coordinated parts: an entry in papers/index.yaml and a Markdown summary under papers/<category>/.

Index entry

The validator requires non-empty title, doi, summary, and status fields.

Field	Contract
`title`	Publication title.
`doi`	DOI beginning with `10.` and a registrant prefix of at least four digits.
`arxiv`	Optional arXiv identifier without a URL.
`drive_id`	Optional private Drive file identifier; absence is a warning.
`summary`	Path relative to `papers/`, including an allowed category.
`status`	`stub`, `draft`, or `reviewed`.

Allowed categories are:

The validator requires present, non-empty values for title, authors, year, doi, and status. The template also defines:

arxiv and drive_id for source identity;
free-form tags;
introduces, extends, models, paradigms, and methods for graph relationships;
cites and cited_by for literature connections; and
relevance for the paper's ecosystem significance.

Allowed non-empty relevance values are foundational, high, medium, and low.

The body follows this durable outline:

Use schema/paper-template.md as the source template rather than copying a possibly older summary.

Status	Meaning
`stub`	Generated or skeletal record; substantive review has not begun.
`draft`	Authored content under review; claims and relationships may change.
`reviewed`	Bibliography, summary, limitations, and relevance have passed repository review.

The index and summary statuses should match. The current validator confirms that both values are allowed but does not compare them with each other.