feat: add OwlSQL v1 M2 Next compiler foundation

[tiagolauer]

Summary

• define compiler diagnostics and the shallow Query IR
• add minimal SELECT parsing and lexical scope resolution
• compile the first SELECT path through the Next compiler without cutting over the public API

Verification

• npm test: 217 passed, 36 skipped
• architecture fitness checks passed
• npm run test:perf: 222,936 instantiations, below the 225,000 budget

Stack

Depends on #358.