add get_current_workspace cloud client method

[zzstoatzz]

this PR adds a cloud client method to read the current workspace. it also deprecates prefect cloud open in favor of the more general prefect dashboard open

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copilot summary

Deprecation and Command Updates:

• src/prefect/cli/cloud/__init__.py: Deprecated the prefect cloud open command and added a deprecation message suggesting the use of prefect dashboard open instead.

Workspace Management:

• src/prefect/cli/cloud/__init__.py: Updated the open function to use an asynchronous context manager for retrieving the current workspace.
• src/prefect/client/cloud.py: Added a new method read_current_workspace to retrieve the current workspace based on the PREFECT_API_URL setting.

Testing Enhancements:

• tests/client/test_cloud_client.py: Added a new test test_read_current_workspace to ensure the read_current_workspace method correctly retrieves the current workspace.

[codspeed-hq]

CodSpeed Performance Report

Merging #15542 will not alter performance

_{Comparing get-current-workspace (add29f1) with main (bc43e28)}

Summary

✅ 3 untouched benchmarks