v5.2.0: additions to the Bullet simulation spine

[stephane-caron]

This release adds several features to the Bullet simulation spine (custom initial configuration, uncertainty on measurements) as well as a random-push wrapper contributed by @Tordjx, thanks 👍

Added

• BulletInterface: Apply custom initial joint configuration, if provided
• BulletInterface: Report velocity of the base link in groundtruth
• BulletInterface: Torque control noise to joint-property configuration
• BulletInterface: Torque measurement noise to joint-property configuration
• BulletInterface: Uncertainty on IMU accelerometer and gyroscope measurements
• Forward command-line arguments to the spine in start_simulation.sh
• ImuData: Add linear velocity field
• envs: Add a random-push wrapper (thanks to @Tordjx)
• examples: Apply an external force to lift an Upkie in sim
• examples: Custom initial state with a non-zero joint configuration
• examples: Simulation with joint friction
• examples: Simulation with sensor noise
• spines: Add variant argument to BulletSpine

Changed

• BulletInterface: Move simulation body poses to sim.bodies
• BulletInterface: Rename internal unit-test getters
• actuation: Log simulation groundtruth to sim

Fixed

• BulletInterface: Fix application of external forces
• CICD: Enable stable-baselines3 environment-check unit tests
• docs: Add missing documentation pages
• docs: Document Gym environment wrappers
• envs: Handle spine errors raised in base env constructor
• envs: Register UpkieServoPositions and UpkieServoTorques environments

Removed

• CICD: Remove pycodestyle as we now use ruff for Python linting
• BulletInterface: Remove unused orientation/position unit-test getters

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This discussion was created from the release v5.2.0.