Retire remaining Data Machine Code integration contracts

[chubes4]

Summary

• remove the remaining Data Machine Code integration contracts owned by wp-coding-agents
• retain only bounded persisted migrations with concrete installed-state evidence
• remove unsupported invented Homeboy hooks and unowned privileged process-probe renames
• update the migration inventory to document final ownership and disposition

Dependency

• depends on Add the required DMC-free workspace gate #559 landing the required DMC-free workspace gate first

Verification

• focused migration inventory, plugin bootstrap, and installation checks passed during independent review
• final acceptance remains gated by Add the required DMC-free workspace gate #559 and repository CI

Closes #528

AI assistance: OpenAI GPT-5.6 Terra using OpenCode was used to implement, independently review, rebase, and verify this change under human orchestration.