A target that fails to start is reported as SAFE

When the target JVM fails before main runs, e.g. with a VerifyError ("Error: Unable to initialize main class"), the SV-COMP driver reports SAFE (== OK). No trace arrives and no branch is explored.

Expected: UNKNOWN. A run that never reached the entry method proves nothing.

Seen while developing #86, where an instrumentation change produced bytecode that HotSpot rejects. The same would happen for any instrumentation bug that breaks verification.