DECLARATIVE-YAML-05: Toggle strict vs open frontmatter

What it demonstrates

Whether unlisted frontmatter keys are rejected (strict) or passed through (open).

Builds on: DECLARATIVE-YAML-04: Make fields optional, defaulted, or nullable

How it’s done

The declarative YAML artifact, verbatim — no code required.

frontmatter:
  strict: true        # unknown keys become a finding (z.strictObject)
  fields:
    type:   { const: task }
    id:     { type: string }
    status: { enum: [open/ready, closed/done] }

Surfaces exercised

• compileFrontmatter(): strict -> z.strictObject vs z.object