A PT_INTERP failure previously exposed only a low-level host error, leaving users unable to tell which guest ABI, runtime root, or loader path LATX had selected.
Report the selected runtime source, the guest PT_INTERP value, the configured candidate from the shared path resolver, the actually attempted host path, a stable failure category, and the underlying detail. Use QEMU error-reporting APIs and direct users to the companion latu-runtime-manager status command.
The diagnostic is emitted only at the interpreter load failure. Successful dynamic guests and static guests retain their existing behavior. Synthetic x86_64 and i386 fixtures cover absolute and relative interpreters, missing, unreadable, corrupt, truncated, valid dynamic, and static cases.
Signed-off-by: Hanlu Li <heuleehanlu@gmail.com>