…rors

51 of 53 TLPGroupBy reproducers in smoke ClickHouse#7 were nth_value(col) emitted with
only 1 argument, rejected by CH with NUMBER_OF_ARGUMENTS_DOESNT_MATCH because
nth_value requires (expr, position). LAG and LEAD have the same 2-arg shape.

The window function AST stores a single argument expression; emitting these
with a synthesised offset would need an args-list field. For now, restrict
the picker to single-arg / no-arg window functions: ROW_NUMBER, RANK,
DENSE_RANK, PERCENT_RANK, CUME_DIST, FIRST_VALUE, LAST_VALUE, SUM, COUNT,
MIN, MAX, AVG. Plan workstream 19 status: NTH_VALUE/LAG/LEAD scaffolded
(Kind enum entry exists) but not actively emitted.

Also tightens addEnumErrors to absorb the MATERIALIZED-cast-to-Enum family
(Conversion from DateTime to Enum, etc.) -- the 1 outlier reproducer in
smoke ClickHouse#7. Pattern is multi-word + qualified to avoid masking legitimate
oracle failures.

…7,8,9,10)

Five self-contained query-structure oracles (default-on, --flag gated, raw-SQL,
no general-fleet hot-path edits -- that emission is a separate gated pass):
- #6  GroupingDecomposition  GROUP BY WITH ROLLUP: detail(GROUPING=0)==plain GROUP BY,
                             super-agg(GROUPING=1)==grand count(), sum(group counts)==grand
- #7  LimitRanking           LIMIT a,b==LIMIT b OFFSET a; LIMIT n prefix-of LIMIT n WITH TIES;
                             LIMIT n BY k <= n rows/key (deterministic total ORDER BY)
- #8  WindowFrame            default frame==explicit RANGE/ROWS UNBOUNDED..CURRENT; lagInFrame
                             ==one-preceding frame (unique-key fixture, single-snapshot compares)
- #9  SemiJoinRewrite        LEFT SEMI==IN, LEFT ANTI==NOT IN (preserved-side projection only
                             per #107073), LEFT ANY JOIN cardinality==left count
- #10 ColumnTransformer      * EXCEPT/APPLY/COLUMNS(regex)==explicit list; DISTINCT ON cardinality

Wired into factory/options/run-sqlancer.sh; mvn compile green. Probe-on-head
(dev-vm): lagInFrame/leadInFrame, empty-frame NULL boundary, WITH TIES/LIMIT BY syntax.