block/item: Give swords and shears per-block mining speeds

[HashimTheArab]

Swords and shears each return a single number for every block: 1.5 from shears, and 1.5 from a sword except on cobweb. Bedrock decides their speed from the block instead — neither tool has a tier speed of its own the way a pickaxe does.

Shears

Bedrock sorts blocks into three tiers for shears:

speed	blocks
15	cobweb, leaves
5	wool
2	vines

Everything else is 1. So shearing wool was more than three times too slow, and cutting leaves or cobweb ten times too slow. minecraft.wiki lists the same numbers under Bedrock breaking speed ("Wool: 5, Leaves: 15, Cobweb: 15").

Swords

15 on cobweb, 30 on bamboo and bamboo saplings, and 1.5 on leaves, vines, moss carpet, pumpkins, melons and cocoa. Everything else is 1 — a sword is no faster than a bare hand on stone.

Only cobweb reached that before. The speed is gated on the block naming the tool effective in its BreakInfo, and no block other than cobweb named a sword, so the old 1.5 default was unreachable everywhere else.

Shape

BaseMiningEfficiency asks the block, through two new interfaces:

type SwordMineable interface{ SwordMiningSpeed() float64 }
type ShearsMineable interface{ ShearsMiningSpeed() float64 }

That keeps the numbers next to the block that owns them, alongside its hardness and harvestability, and leaves BreakDuration untouched. The blocks that answer also name the tool in their Effective predicate, which is what that predicate already means — "can be mined more effectively with the tool passed than with an empty hand" — and is true of a sword on leaves.

anyEffective is a small combinator for the blocks that now have two tool types, replacing the hand-written closures.

The resulting times line up with those published for Bedrock: wool with shears 0.25s, cobweb with shears 0.4s, leaves with shears 0.05s, leaves with a sword 0.2s against 0.3s bare-handed, and a pumpkin with a sword 1s.

Not covered

Glow lichen, chorus plant, chorus flower and big dripleaf also take 1.5 from a sword in Bedrock. There are no such blocks yet, so there is nothing to hang the method on.