adds scstr_t to modules.md + fixes parenthesis bug in sstrsplit_a macro scstr_t-final

use 'convert' as more precise term than 'cast' for the conversion from sstr_t to scstr_t

unifies naming of sstr_t related and scstr_t related functions

adds remaining documentation for the scstr functions

overflow of sstrnlen should return SIZE_MAX instead of zero

adjusts documentation of UCX string types, converters, and constructors

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mercurial