Improve Reachability for Blocks Ending with syscall abort/sol_panic_

[LeoQ7]

Currently, the implementation mistakenly assumes that lbb_42 is reachable from lbb_41 in the following case:

lbb_41:
    syscall abort
lbb_42:

As a result, lbb_41 is incorrectly added to the sources of lbb_42, and lbb_42 is added to the destinations of lbb_41. However, this is inaccurate since execution does not continue past syscall abort.

This PR corrects the reachability to ensure that blocks terminating with syscall abort are properly handled.