transmute.py: convert_all_gems_to_perfect() chains all four gem tiers
(chipped->flawed->standard->flawless->perfect) by calling the existing
_run_gem_transmutes_lod for each tier in order. Result gems from each
pass land back in stash and feed the next pass.
testbed.py: gems_all scenario triggers convert_all_gems_to_perfect with
stash open; also adds missing return 0 to _gems().
hermes.py: fix UnicodeEncodeError on cp1252 terminals when the LLM
response contains non-ASCII characters (arrows, bullets, etc.).
Co-Authored-By: Claude Sonnet 4.6 <[email protected]>