Backend: DO_TRY compounds now use a virtual _TRY_BODY wrapper with LR
layout for the try body, while DO_CATCH/DO_FINALLY stack below as
separate sections (TB). Edges from DO_TRY are skipped like route-level
handler edges. Removes ELK-v2 debug logging.
Frontend: _TRY_BODY renders as transparent wrapper, DO_CATCH as red
tinted section, DO_FINALLY as teal section. DO_FINALLY color changed
from red to teal (completion handler, not error).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>