claude@clouddev1
dd37a1cbfc
Implements the six ADR-0032 §10.3 output-column derivation rules at CTE body-frame exit, populating the placeholder CteBinding's columns. Unblocks `diagnostic.cte_arity_mismatch` (which compares declared col-list arity vs derived projection arity) and the upcoming qualified-prefix completion in 2e proper. - `WalkContext::pending_cte_harvest`: bookkeeping for an in-progress CTE harvest, armed by writes_cte_name + extended by cte_column idents, consumed by the next walk_scoped_subgrammar invocation (CTE syntax has no intervening ScopedSubgrammar, so timing is deterministic). Cleared on every walk_scoped_subgrammar entry to prevent stale state surviving a speculative walk rollback. - `run_cte_harvest`: post-walk path-scan classifier that reconstructs the body's first leg's projection-list and applies the six derivation rules. Compound bodies take columns from the first leg per spec; recursive CTE bodies take the non-recursive (first) leg. Optional (col-list) renames positionally with preserved types. - `expand_binding`: bridges a TableBinding to a CteColumn list, resolving CTE-source bindings (empty columns + table-name matches an in-scope CteBinding) through to the CTE's harvested columns. Enables sibling CTEs to project correctly: in \`WITH a AS (...), b AS (SELECT * FROM a) ...\`, b's harvest sees a's derived columns through the body's from_scope binding. - `WalkContext::pending_diagnostics`: accumulator for diagnostics emitted DURING the walk by node handlers with context the post-walk passes can't reconstruct. Drained by the top-level walk function on both match and non-match paths so a re-used context can't leak entries between walks. Test totals: 1399 → 1414 passing (+15: 10 derivation rules + 1 sibling CTE + 4 arity match/mismatch tests). Clippy clean.