Add the --abort-on-malformed-sstable-error command-line option and the
supporting infrastructure. When set, any malformed sstable error will
abort the process and generate a coredump instead of throwing an
exception. This is useful for debugging memory corruption that may
manifest as apparent sstable corruption.
The implementation introduces:
- throw_malformed_sstable_exception() and throw_bufsize_mismatch_exception()
helper functions in sstables/sstables.cc, which check the new flag and
either abort (with logging) or throw the appropriate exception.
- set_abort_on_malformed_sstable_error() / abort_on_malformed_sstable_error()
to control the per-process atomic flag.
- abort_on_malformed_sstable_error config option (LiveUpdate, default false)
wired up in main.cc alongside abort_on_internal_error.
Call-site migration will follow in subsequent commits.