While working on WT-13936 and WT-13937, I discovered that several macros within reconcile_inline.h are only used within the reconciliation module and should therefore be made private. I'm proposing to move WT_CROSSING_MIN_BND, WT_CROSSING_SPLIT_BND, and WT_CHECK_CROSSING_BND to the reconcile_private.h header file and rename these macros using the WTI_XXX prefix to clearly indicate their internal use.

The scope of this ticket is to move the above-mentioned macros and others, if any, to the reconcile_private.h header file and rename these macros using the WTI_XXX prefix.