Q: iron_smelt (iron_ore + wood → iron_ingot) and gold_smelt
(gold + wood → gold_ingot) recipes added at Smelter, using the
existing ingredient2 buffer mechanism. New TYPE_IRON_INGOT and
TYPE_GOLD_INGOT item types (procedural hue-hash draw for now).
R: new Recipe.target_workbench field (StringName, empty = any matching
skill) round-trips through to_dict/from_dict. Workbench bill picker
filters by both required_skill AND target_workbench vs lower-cased
label_text. plank → carpenter, stone_block/iron_smelt/gold_smelt →
smelter, flour → millstone. Cooking-only recipes (bread, meal) stay
unrestricted since Hearth is the only cooking workbench.
9 recipes total now, 4 distinct workbench routes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The mode OptionButton and remove Button both called _populate_bills()
from inside their own signal callbacks. _populate_bills() rebuilds the
bill list — freeing the very widget mid-emit, which crashes Godot.
Defer the rebuild via call_deferred("_populate_bills") so it runs
after the signal frame completes. Reproduced by user changing a bill
from FOREVER → "Do until 10".
