The right/left wings and feet of a chicken cannot be independently retextured

The right/left wings and feet of a chicken cannot be independently retextured from one another, making them always look the same. This is limiting the player's resource pack capability and creativity.

Steps to Reproduce:

1. Download and apply the following resource pack:
   Chicken.zip
2. Spawn a chicken

Observed Behavior:

Both of the wings and feet of the chicken will look entirely purple, despite the player seemingly only modifying one wing and one foot in the UV map.

Expected Result:

Only one wing and one foot would be altered, since that is what the player intended to change. The current behavior is unexpected and not resource pack friendly.

Screenshots/Videos:

Notes:

Related independent retexture issues:
MC-265345 MC-265343 MC-145334 MC-270516 MC-270517 MC-269523 MC-271304 MC-271305 MC-271330 MC-271354 MC-271334 MC-271355 MC-271368 MC-271383