refactor(protocol): split maintainability hotspots

[hishamkaram]

Summary

• Splits protocol delegation and domain files while preserving wire ownership in the protocol repo.

Commits

• 2237866fc3c0 refactor(protocol): split delegation wire types by domain (14 files)
• de973a3d3b3f refactor(protocol): keep protocol domain files below gate (6 files)
• 2832ab2c269e chore(graph): refresh protocol graph metadata (6 files)
• fe9758ac0ca2 chore(graph): refresh graph after ship commits (4 files)

Verification

• Branch guard passed before push for ship/maintainability-overhaul.
• Git hooks ran during local commits; final graph drift was committed separately where hook rebuilds changed graph output.
• Workspace gates passed before shipping: make maintainability-audit, make skill-quality-policy, and ./scripts/doctor.sh --strict-protection --allow-dirty --allow-ahead.
• Earlier full affected test/lint/build gates passed during the maintainability review loop; root codex review --uncommitted reported no blocking findings.