Adds mock interfaces to enable unit-testing and isolated benchmaking.

[AntoineRichard]

Description

Add mock interfaces for PhysX's TensorAPI views as well as for the base asset/sensor abstractions. These are targeted for towards unit testing and benchmarking without starting kit.

New Features:

• MockArticulationData & MockArticulation
• MockRigidObjectData & MockRigidObject
• MockRigidObjectCollectionData & MockRigidObjectCollection
• MockIMUData & MockIMU
• MockFrameTransformerData & MockFrameTransformer
• MockContactSensorData & MockContactSensor
• MockRigidBodyView - Mock for physx.RigidBodyView
• MockArticulationView - Mock for physx.ArticulationView
• MockRigidContactView - Mock for physx.RigidContactView
• Pre-configured factories for quadruped (12 DOFs) and humanoid (21 DOFs) robots
• Patching utilities (context managers and decorators) for easy test setup
• Tests to ensure coverage is correct

Type of change

• New feature (non-breaking change which adds functionality)
• Documentation update

Checklist

• I have read and understood the contribution guidelines
• I have run the pre-commit checks with ./isaaclab.sh --format
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have updated the changelog and the corresponding version in the extension's config/extension.toml file
• I have added my name to the CONTRIBUTORS.md or my name already exists there

[greptile-apps]

Too many files changed for review. (166 files found, 100 file limit)