feat(rigging-UI): add rigging pie menu

[GixoXYZ]

Describe your idea
Add rigging pie menu in specific modes such as "Pose Mode" and "Weight Paint Mode" to quickly select bones, manipulate weight paintings and more.

TO-DO:

• Add basic pie menu with weight painting and bone selection sections.
• Generic bone selection logic that works with both GBH Tool and non GBH Tool armatures.
• Make sure that the buttons are disabled dynamically in unsupported conditions.
  • Disable pie menu weight painting related buttons if the object has no vertex groups or all are deleted.
  • Make sure UI buttons are made in a way that won't be accidentally selectable when disabled. Or add a safety measure to the logic.

Potential features:

• Select similar bones by their position in the chain.
• Add bone constraints to the selected bones.