Mazu's Furnaces

## 0.2.0

New
- Each fuel heats at its own speed: better fuels heat up faster. The multiplier shows in the fuel tooltip while a furnace is open.
- Recycling: iron and gold tools, armor and buckets melt in the Bloomery, Iron Furnace and Nether Forge, returning metal based on remaining durability (26.x also copper and spears).
- Iron Furnace: with all 9 slots holding the same ore, each batch takes one from every slot (9 ores → 12 ingots).
- Coal in the charge gives sulfur slag in the Iron Furnace and Nether Forge, whatever the fuel.
- The Obsidian Lining can't be removed while the fire is lit.

Changes

- Netherite ingot: 4 scrap + 4 gold, each in its own slot.
- All furnaces heat at 1 °C/tick; the Iron Furnace at 1.5 °C/tick.
- Iron smelts with any fuel hot enough; burning coal still gives sulfur slag.
- Gold tools no longer turn into nuggets in the Clay Kiln (use recycling).
- The empty bucket from lava used as fuel stays in its slot and is never recycled.
- Bloomery, Iron Furnace and Nether Forge keep working on residual heat after the fire goes out, like the Clay Kiln.

Fixes
- Clay Kiln item rendering with broken textures in hand and on the ground.
- Charge furnace thermometer now scales to each furnace's limit.
- 1.20.1: broken Clay Kilns without cracks now stack with new ones.