PHOENIX-8018: Disable global index read repair for ROW_SIZE() and RAW_ROW_SIZE() scans (#2646)

* PHOENIX-8018: Disable index read repair for row-size scans

Keep read repair disabled for index rebuilds, and skip enabling it for ROW_SIZE() and RAW_ROW_SIZE() scans. These functions should inspect stored index state without performing repair.

Generated-by: Pi 1.4.0 (gpt-6-luna)

* Add row size coverage for unverified index rows