Autoformat families are profile-adjacent input-assist surfaces

Question

How should Plate model block shorthand, inline mark autoformat, and text substitution autoformat?

Decision

Treat them as profile-adjacent input-assist surfaces, not parser law.

Split them into at least three families:

• block shorthand autoformat
• inline mark autoformat
• text-substitution autoformat

Why

• they change typing behavior and editor feel
• they do not define the canonical parse or serialize contract by themselves
• different families want different authorities and different guardrails
• some symbols are pair-on-type
• some are selection-wrap-first
• some are plain text substitutions with no markdown ownership at all

Consequences

• editor-behavior law should not flatten them into one generic "autoformat" row
• protocol rows should split block, mark, and text-substitution scenarios
• parity should track them as profile-adjacent input-assist surfaces instead of pretending they are the core markdown parse contract