The LABS-19 prototype code uses uint32_t to type object ids.  More recent code for tracking the current object id in the tiered layer uses uint64_t types.  We should pick one or the other and change internal interfaces appropriately.

This would have been part of WT-7514, but it became clear it may have some cascading effects and should be treated as its own ticket.

There is a FIXME comment in the code at one of the cast operations, there is likely to be other fallout from strict compilers.