DECLARATIVE-YAML-02: Constrain with enum and const

What it demonstrates

Pinning a field to a fixed literal (const) or a closed set of allowed values (enum).

Builds on: DECLARATIVE-YAML-01: Validate one required frontmatter field by type

How it’s done

The declarative YAML artifact, verbatim — no code required.

frontmatter:
  fields:
    type:
      const: decision
    status:
      enum: [open/ready, in-progress/active, closed/done]

Surfaces exercised

• schema.ts base(): const -> z.literal()
• enum -> z.enum()