Adds aysnc event cleanup before Mimic shutdown (#515)

# Description

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Adds a cleanup of remaining async events in the Mimic data generation
code. The cleanup cancels remaining events after the environment is
closed and prior to sim app shutdown. This prevents left over events
from trying to use the env after it is closed.

## Type of change

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applicable. -->

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

## 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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scripts/imitation_learning/isaaclab_mimic/generate_dataset.py

@@ -127,7 +127,7 @@ def main():
     )
 
     try:
-        asyncio.ensure_future(asyncio.gather(*async_components["tasks"]))
+        data_gen_tasks = asyncio.ensure_future(asyncio.gather(*async_components["tasks"]))
         env_loop(
             env,
             async_components["reset_queue"],
@@ -137,6 +137,16 @@ def main():
         )
     except asyncio.CancelledError:
         print("Tasks were cancelled.")
+    finally:
+        # Cancel all async tasks when env_loop finishes
+        data_gen_tasks.cancel()
+        try:
+            # Wait for tasks to be cancelled
+            async_components["event_loop"].run_until_complete(data_gen_tasks)
+        except asyncio.CancelledError:
+            print("Remaining async tasks cancelled and cleaned up.")
+        except Exception as e:
+            print(f"Error cancelling remaining async tasks: {e}")
 
 
 if __name__ == "__main__":

source/isaaclab_mimic/config/extension.toml

 [package]
 
 # Semantic Versioning is used: https://semver.org/
-version = "1.0.9"
+version = "1.0.10"
 
 # Description
 category = "isaaclab"

source/isaaclab_mimic/docs/CHANGELOG.rst

 Changelog
 ---------
 
+1.0.10 (2025-07-08)
+~~~~~~~~~~~~~~~~~~
+
+Changed
+^^^^^^^
+
+* Updated generate dataset script to cancel remaining async tasks before closing the simulation app.
+
+
 1.0.9 (2025-05-20)
 ~~~~~~~~~~~~~~~~~~