refactor: cut SELECT inference over to Next in M3

[tiagolauer]

Summary

• migrate SELECT sources, joins, expressions, predicates, parameters, and subquery scopes
• isolate SELECT dialect capabilities
• route supported SELECT inference through the Next compiler

Verification

• npm test: 217 passed, 36 skipped
• architecture fitness checks passed
• npm run test:perf: 223,663 instantiations, below the 225,000 budget

Stack

Depends on #359.