Refresh consolidated edit command documentation

[deverman]

Summary

• update the README and discovery copy for the nine-tool source catalog and two consolidated edit tools
• distinguish the current source interface from the released v0.10.1-beta Homebrew interface
• record the breaking command migration under Unreleased
• remove completed Upgrade Swift MCP SDK to 0.12.1 and migrate deprecated text responses #75/Consolidate task and project edit commands into a smaller MCP and CLI surface #91 work from active roadmap sequencing
• align mutation contracts, checklists, and inbox architecture with operation-based edits

Validation

• swift run focusrelay-dev validate --impact docs
• Markdown links valid
• whitespace checks clean
• stale-language scan leaves legacy command names only in the explicit migration table and historical records
• independent final review: no findings

Closes #136