Adds galbot stack cube tasks, with left_arm_gripper and right_arm_suction, using RMPFlow controller (#3210)

# Description

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Adds galbot_stack_cube tasks and mimic tasks, using RMPFlow controller:
- add galbot robot config and .usd asset
- add RMPFlowAction and RMPFlowActionCfg
- add motion_policy_configs and .urdf for both 'galbot_left_arm_gripper'
and 'galbot_right_arm_suction'
- add new task: galbot stack_rmp_rel_env_cfg
- add new mimic task: galbot_stack_rmp_abs/rel_mimic_env
- add mdp.observations/terminations/events for galbot: support
gripper_state checking for both suction_cup and parallel_gripper, get
obs_in_base_frame
- add gripper_configs (gripper_joint_names, gripper_open_val,
gripper_threshold) in galbot/franka tasks: to make mdp functions
universal to varied robots
- fix a bug (eef_name) in franka_stack_ik_rel_mimic_env.py
- add new device_name in se3_spacemouse.py

Notes: This PR relies on PR
(https://github.com/isaac-sim/IsaacLab/pull/3174) for surface gripper
support in manager-based workflow.

You can test the whole gr00t-mimic workflow by:
1. record demos:
`./isaaclab.sh -p scripts/tools/record_demos.py --task
Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-v0 --teleop_device
spacemouse --num_demos 1 --device cpu --dataset_file
datasets/recorded_demos_galbot_suction_rel.hdf5`
2. replay demos:
`./isaaclab.sh -p scripts/tools/replay_demos.py --task
Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-v0 --num_envs 1
--device cpu --dataset_file
datasets/recorded_demos_galbot_suction_rel.hdf5`
3. annotate demos:
`./isaaclab.sh -p
scripts/imitation_learning/isaaclab_mimic/annotate_demos.py --task
Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-Rel-Mimic-v0 --auto
--device cpu --input_file
datasets/recorded_demos_galbot_suction_rel.hdf5 --output_file
datasets/annotated_demos_galbot_suction_rel.hdf5`
4. generate dataset:
`./isaaclab.sh -p
scripts/imitation_learning/isaaclab_mimic/generate_dataset.py --task
Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-Rel-Mimic-v0 --num_envs
16 --device cpu --generation_num_trials 10 --input_file
datasets/annotated_demos_galbot_suction_rel.hdf5 --output_file
datasets/generated_demos_galbot_suction_rel.hdf5`

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## Type of change

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applicable. -->

- Bug fix (non-breaking change which fixes an issue)
- New feature (non-breaking change which adds functionality)

## Screenshot
<img width="1428" height="281" alt="environments_galbot"
src="https://github.com/user-attachments/assets/b603bc60-7ff3-44e8-bf41-ab8126a753ec"
/>


## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] 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

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---------
Signed-off-by: rebeccazhang0707 <168459200+rebeccazhang0707@users.noreply.github.com>
Signed-off-by: Kelly Guo <kellyg@nvidia.com>
Co-authored-by: Kelly Guo <kellyg@nvidia.com>