`SORT TO <file> [ON <key-list>] [FOR ...] [WHILE ...] [NEXT ...]
[RECORD ...] [REST] [ALL]` joins COPY in being a real preprocessor
rewrite to a function call. New RTL primitive __dbSort:
* Buffer visible source records (FOR/WHILE/NEXT/RECORD/REST same
as __dbCopy).
* Multi-key stable insertion sort. Each key may carry `/D` for
descending; ascending otherwise. /A and unknown suffixes fall
through as ascending. Comparison delegates to the existing
compareValues helper in sqlscan.go (numeric / string / NIL-aware).
* Create destination DBF with the source's struct, append rows in
sorted order, restore source selection.
Parser cleanup: SORT removed from the IDENT-statement no-op switch.
Gates green:
go test ./... : PASS
FiveSql2 SQL:1999 : 43/43
Harbour compat : 56/56
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>