PASS: intro is stripped to plain text and bounded to 500 characters
PASS: summary is bounded to 1,000 characters
PASS: Planning accepts text/checklist and rejects image-text and wholly empty sections
PASS: section heading/body are bounded and markup is removed
PASS: checklist is bounded to 20 items of 240 characters each
PASS: invalid nonce leaves existing guide metadata unchanged
PASS: user without edit_post capability cannot alter guide metadata with a valid nonce
PASS: category changed before Update enables the Outdoors image-text layout
PASS: empty optional fields are deleted from metadata
PASS: malformed legacy metadata is safely omitted during rendering
PASS: unknown category renders no guide article
PASS: image-text output uses native responsive attachment markup
Success: Field Atlas runtime checks passed: 12; skipped: 0.