Equivalence between KeyImpl and TypedKeyImpl is not symmetric

[NichtStudioCode]

Expected behavior

Object#equals's contract requires:

It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.

Observed/Actual behavior

Equivalence between TypedKeyImpl and KeyImpl is not symmetric

Steps/models to reproduce

Key key = Key.key("minecraft:stone");
TypedKey<ItemType> typedKey = TypedKey.create(RegistryKey.ITEM, key);
System.out.println(key.equals(typedKey)); // true
System.out.println(typedKey.equals(key)); // false

Plugin and Datapack List

None

Paper version

This server is running Paper version 1.21.11-126-main@3f5728e (2026-02-28T11:49:07Z) (Implementing API version 1.21.11-R0.1-SNAPSHOT)

Other

In my opinion TypedKey shouldn't extend Key. But since it is too late to change this now, I think the problem could be solved by:

1. In TypedKeyImpl, override equals and check if the other object is also a TypedKey. If so, additionally compare registry key. Otherwise, only compare namespace and value.
2. In TypedKeyImpl, override hashCode and replace its implementation with that of KeyImpl (from adventure), such that the registry key has no influence on the hash code and equal keys have equal hash codes.

[gunjanjaswal]

Opened #14025. It overrides equals/hashCode on TypedKeyImpl so a TypedKey is symmetric with an equal plain Key and hashes the same, while typed-vs-typed keeps the registry distinction. Flagged the transitivity tradeoff in the PR in case you'd prefer key-only equality.