Query planner: name resolution, WHERE analysis, cost model, join ordering.
Implements:
- Compound SELECT ORDER BY resolution (§19 quirk: first SELECT wins)
- Cost model for access paths in page reads (§10.5)
- Index usability analysis for WHERE terms (§10.5)
- Bounded beam search join ordering — NGQP-style (§10.5)
Note: AST-to-VDBE compilation is an integration concern and lives above the planner layer per the workspace layering rules (bd-1wwc).