Fixes the import issues in stacking manipulation task (#3398)

# Description

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Fixes the import issues via "path:Module" in below files, which will not
import all modules/dependencies unless in use
```
- isaaclab_tasks/manager_based/manipulation/stack/config/galbot/__init__.py
- isaaclab_tasks/manager_based/manipulation/stack/config/ur10_gripper/__init__.py
- isaaclab_mimic/envs/__init__.py
```


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## Type of change

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- Bug fix (non-breaking change which fixes an issue)



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## 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
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source/isaaclab_mimic/isaaclab_mimic/envs/__init__.py

@@ -16,13 +16,6 @@ from .franka_stack_ik_rel_mimic_env_cfg import FrankaCubeStackIKRelMimicEnvCfg
 from .franka_stack_ik_rel_skillgen_env_cfg import FrankaCubeStackIKRelSkillgenEnvCfg
 from .franka_stack_ik_rel_visuomotor_cosmos_mimic_env_cfg import FrankaCubeStackIKRelVisuomotorCosmosMimicEnvCfg
 from .franka_stack_ik_rel_visuomotor_mimic_env_cfg import FrankaCubeStackIKRelVisuomotorMimicEnvCfg
-from .galbot_stack_rmp_abs_mimic_env import RmpFlowGalbotCubeStackAbsMimicEnv
-from .galbot_stack_rmp_abs_mimic_env_cfg import (
-    RmpFlowGalbotLeftArmGripperCubeStackAbsMimicEnvCfg,
-    RmpFlowGalbotRightArmSuctionCubeStackAbsMimicEnvCfg,
-)
-from .galbot_stack_rmp_rel_mimic_env import RmpFlowGalbotCubeStackRelMimicEnv
-from .galbot_stack_rmp_rel_mimic_env_cfg import RmpFlowGalbotLeftArmGripperCubeStackRelMimicEnvCfg
 
 ##
 # Inverse Kinematics - Relative Pose Control
@@ -104,18 +97,22 @@ gym.register(
 
 gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-Rel-Mimic-v0",
-    entry_point="isaaclab_mimic.envs:RmpFlowGalbotCubeStackRelMimicEnv",
+    entry_point=f"{__name__}.galbot_stack_rmp_rel_mimic_env:RmpFlowGalbotCubeStackRelMimicEnv",
     kwargs={
-        "env_cfg_entry_point": galbot_stack_rmp_rel_mimic_env_cfg.RmpFlowGalbotLeftArmGripperCubeStackRelMimicEnvCfg,
+        "env_cfg_entry_point": (
+            f"{__name__}.galbot_stack_rmp_rel_mimic_env_cfg:RmpFlowGalbotLeftArmGripperCubeStackRelMimicEnvCfg"
+        ),
     },
     disable_env_checker=True,
 )
 
 gym.register(
     id="Isaac-Stack-Cube-Galbot-Right-Arm-Suction-RmpFlow-Rel-Mimic-v0",
-    entry_point="isaaclab_mimic.envs:RmpFlowGalbotCubeStackRelMimicEnv",
+    entry_point=f"{__name__}.galbot_stack_rmp_rel_mimic_env:RmpFlowGalbotCubeStackRelMimicEnv",
     kwargs={
-        "env_cfg_entry_point": galbot_stack_rmp_rel_mimic_env_cfg.RmpFlowGalbotRightArmSuctionCubeStackRelMimicEnvCfg,
+        "env_cfg_entry_point": (
+            f"{__name__}.galbot_stack_rmp_rel_mimic_env_cfg:RmpFlowGalbotRightArmSuctionCubeStackRelMimicEnvCfg"
+        ),
     },
     disable_env_checker=True,
 )
@@ -126,18 +123,22 @@ gym.register(
 
 gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-Abs-Mimic-v0",
-    entry_point="isaaclab_mimic.envs:RmpFlowGalbotCubeStackAbsMimicEnv",
+    entry_point=f"{__name__}.galbot_stack_rmp_abs_mimic_env:RmpFlowGalbotCubeStackAbsMimicEnv",
     kwargs={
-        "env_cfg_entry_point": galbot_stack_rmp_abs_mimic_env_cfg.RmpFlowGalbotLeftArmGripperCubeStackAbsMimicEnvCfg,
+        "env_cfg_entry_point": (
+            f"{__name__}.galbot_stack_rmp_abs_mimic_env_cfg:RmpFlowGalbotLeftArmGripperCubeStackAbsMimicEnvCfg"
+        ),
     },
     disable_env_checker=True,
 )
 
 gym.register(
     id="Isaac-Stack-Cube-Galbot-Right-Arm-Suction-RmpFlow-Abs-Mimic-v0",
-    entry_point="isaaclab_mimic.envs:RmpFlowGalbotCubeStackAbsMimicEnv",
+    entry_point=f"{__name__}.galbot_stack_rmp_abs_mimic_env:RmpFlowGalbotCubeStackAbsMimicEnv",
     kwargs={
-        "env_cfg_entry_point": galbot_stack_rmp_abs_mimic_env_cfg.RmpFlowGalbotRightArmSuctionCubeStackAbsMimicEnvCfg,
+        "env_cfg_entry_point": (
+            f"{__name__}.galbot_stack_rmp_abs_mimic_env_cfg:RmpFlowGalbotRightArmSuctionCubeStackAbsMimicEnvCfg"
+        ),
     },
     disable_env_checker=True,
 )

source/isaaclab_tasks/isaaclab_tasks/manager_based/manipulation/stack/config/galbot/__init__.py

@@ -5,9 +5,6 @@
 
 
 import gymnasium as gym
-import os
-
-from . import stack_rmp_rel_env_cfg
 
 ##
 # Register Gym environments.
@@ -21,7 +18,7 @@ gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-RmpFlow-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_rmp_rel_env_cfg.RmpFlowGalbotLeftArmCubeStackEnvCfg,
+        "env_cfg_entry_point": f"{__name__}.stack_rmp_rel_env_cfg:RmpFlowGalbotLeftArmCubeStackEnvCfg",
     },
     disable_env_checker=True,
 )
@@ -31,7 +28,7 @@ gym.register(
     id="Isaac-Stack-Cube-Galbot-Right-Arm-Suction-RmpFlow-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_rmp_rel_env_cfg.RmpFlowGalbotRightArmCubeStackEnvCfg,
+        "env_cfg_entry_point": f"{__name__}.stack_rmp_rel_env_cfg:RmpFlowGalbotRightArmCubeStackEnvCfg",
     },
     disable_env_checker=True,
 )
@@ -44,7 +41,7 @@ gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-Visuomotor-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_rmp_rel_env_cfg.RmpFlowGalbotLeftArmCubeStackVisuomotorEnvCfg,
+        "env_cfg_entry_point": f"{__name__}.stack_rmp_rel_env_cfg:RmpFlowGalbotLeftArmCubeStackVisuomotorEnvCfg",
     },
     disable_env_checker=True,
 )
@@ -56,7 +53,9 @@ gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-Visuomotor-Joint-Position-Play-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_rmp_rel_env_cfg.GalbotLeftArmJointPositionCubeStackVisuomotorEnvCfg_PLAY,
+        "env_cfg_entry_point": (
+            f"{__name__}.stack_rmp_rel_env_cfg:GalbotLeftArmJointPositionCubeStackVisuomotorEnvCfg_PLAY"
+        ),
     },
     disable_env_checker=True,
 )
@@ -68,7 +67,7 @@ gym.register(
     id="Isaac-Stack-Cube-Galbot-Left-Arm-Gripper-Visuomotor-RmpFlow-Play-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_rmp_rel_env_cfg.GalbotLeftArmRmpFlowCubeStackVisuomotorEnvCfg_PLAY,
+        "env_cfg_entry_point": f"{__name__}.stack_rmp_rel_env_cfg:GalbotLeftArmRmpFlowCubeStackVisuomotorEnvCfg_PLAY",
     },
     disable_env_checker=True,
 )

source/isaaclab_tasks/isaaclab_tasks/manager_based/manipulation/stack/config/ur10_gripper/__init__.py

@@ -5,8 +5,6 @@
 
 import gymnasium as gym
 
-from . import stack_ik_rel_env_cfg
-
 ##
 # Register Gym environments.
 ##
@@ -20,7 +18,7 @@ gym.register(
     id="Isaac-Stack-Cube-UR10-Long-Suction-IK-Rel-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_ik_rel_env_cfg.UR10LongSuctionCubeStackEnvCfg,
+        "env_cfg_entry_point": f"{__name__}.stack_ik_rel_env_cfg:UR10LongSuctionCubeStackEnvCfg",
     },
     disable_env_checker=True,
 )
@@ -29,7 +27,7 @@ gym.register(
     id="Isaac-Stack-Cube-UR10-Short-Suction-IK-Rel-v0",
     entry_point="isaaclab.envs:ManagerBasedRLEnv",
     kwargs={
-        "env_cfg_entry_point": stack_ik_rel_env_cfg.UR10ShortSuctionCubeStackEnvCfg,
+        "env_cfg_entry_point": f"{__name__}.stack_ik_rel_env_cfg:UR10ShortSuctionCubeStackEnvCfg",
     },
     disable_env_checker=True,
 )

source/isaaclab_tasks/isaaclab_tasks/manager_based/manipulation/stack/config/ur10_gripper/agents/__init__.py

-# Copyright (c) 2022-2025, The Isaac Lab Project Developers (https://github.com/isaac-sim/IsaacLab/blob/main/CONTRIBUTORS.md).
-# All rights reserved.
-#
-# SPDX-License-Identifier: BSD-3-Clause