The A2UI work now lives on dedicated phase branches, so main should go back to the non-A2UI baseline instead of carrying the feature work directly.
This revert removes the contiguous A2UI range from main while preserving the work on codex/a2ui-phase-1-readonly, codex/a2ui-phase-2-actions, and codex/a2ui-phase-3-full.
Constraint: Main already had the A2UI range published, so use a revert instead of rewriting history
Rejected: Force-push a rewritten main history | would rewrite published commits and break downstream clones
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Keep future A2UI work on the dedicated phase branches until you intentionally merge it back
Tested: Sequential fast-forward replay of phase branches from 5bfd4a18 to 107ccff0; tree equality against 5bfd4a18 after revert
Not-tested: Full repository test suite before push
