Copper Age Backport Durability Fix

A small Minecraft mod that fixes copper armor having no durability in Copper Age Backport on Minecraft 1.21.1.

What it does

Copper Age Backport 0.1.4 and earlier register the copper helmet, chestplate, leggings, and boots without a durability value, so the items never take damage and never break. This mod fixes that so the items get their proper vanilla copper armor durability values:

Item	Max durability
Copper helmet	121
Copper chestplate	176
Copper leggings	165
Copper boots	143

The fix self-disables on Copper Age Backport > 0.1.4, so it becomes a no-op the moment the upstream fix ships.

Compatibility

• Minecraft: 1.21.1
• Loaders: NeoForge (21.1.186+) and Fabric (loader 0.16+, Java 21+)
• Required dependency: Copper Age Backport <= 0.1.4 (the mod refuses to load without it; on newer Copper Age Backport versions it loads but skips its mixin)