merge: combine local Round-22 build system commit with origin/0.3.1 SUBMODULE-NORMALIZATION doc

Local had the SUBMODULE-NORMALIZATION doc + Round-22 build system commit
uncommitted; origin had the same doc pre-Round-22. This merge combines
both into a single linear history.

(NO AI attribution)

# Conflicts:
#	local/docs/SUBMODULE-NORMALIZATION-2026-07-13.md
This commit is contained in:
2026-07-14 13:34:52 +09:00