Reduce string duplication from assertion messages

[sethrj]

Inspired by @esseivaju 's example in #1325 , this defines external constant strings for "runtime error" types to both reduce library size and to avoid "magic constants" (i.e. requiring that special string values in one file match string values in another).

HIP/frontier (ORANGE ndebug):

Library	Before	After
libcorecel.a	1613066	1606148
libgeocel.a	902558	898838
liborange.a	4122526	4095566
libceleritas.a	11385000	11295664
libaccel.a	869100	863828

CUDA/wildstyle (ORANGE reldeb):

Library	Before	After
libcorecel.a	17431736	17415056
libgeocel.a	10777392	10776984
liborange.a	54714576	54682904
libceleritas.a	182853472	181899976
libaccel.a	21292144	21290984

Unfortunately I'm not able to use static inline constexpr for the CUDA/HIP printf statements:

/home/s3j/Code/celeritas/src/corecel/Assert.hh(516): error: An inline __device__/__constant__/__managed__ variable must have internal linkage when the program is compiled in whole program mode (-rdc=false)

see this llvm bug report for details.

[esseivaju]

Unfortunately I'm not able to use static inline constexpr for the CUDA/HIP printf statements:

They also mention it here, maybe that will be supported one day