Fix set equipment translation in 1.20.5->.3 and replace magic values

[FlorianMichael]

Closes #862

[kennytv]

It's not so much the min byte value that is used here as it is the last available bit (1 << 7). Same thing with max value, what's important is that it strips the last bit/only keep the bits until then, not that it's the max positive value (their hex representation doesn't show that either, but changing it to min/max value isn't better)

[FlorianMichael]

Then we should at least use the decimal values MC also has to prevent confusion

[kennytv]

It's only that in decompiled code because of proguard and constant inlining during compilation, the only representation that will show it accuratetly is 1 << 7. 0x7f is okay because the alternative would be (byte) ~ (1 << 7), and hex f with or without a tailing 7 are more obvious tellers of a number with all bits set up to a point

[FlorianMichael]

Hm yeah, thanks for clarification