Closes #5344: ArkoudaExtensionArray.view

[ajpotts]

Summary
This PR implements view() for ArkoudaExtensionArray, aligning Arkouda’s pandas ExtensionArray behavior with pandas’ expectations around shallow copies. This resolves failures triggered by pandas internals (e.g. BlockManager.copy(deep=False)) that previously raised NotImplementedError.

The new implementation returns a shallow wrapper that shares the same underlying Arkouda server-side data while preserving optional internal metadata. No data is materialized or copied unless an explicit dtype conversion is requested.

Key Changes

• Implemented ArkoudaExtensionArray.view() with pandas-compatible semantics
• Delegates to astype(dtype, copy=False) when a different dtype is requested
• Shares underlying _data while copying optional attributes by reference (_mask, _categories, _codes, _na_value, _cache)
• Added comprehensive unit tests covering:
  • Shallow-copy semantics
  • Optional attribute handling
  • dtype delegation behavior
  • Regression case for pandas DataFrame construction
• Improved test diagnostics by replacing print with warnings.warn
• Minor import cleanup for consistency

Why This Matters
Pandas frequently relies on .view() for shallow copies during internal operations. Without this method, valid workflows (e.g. constructing a DataFrame from a Series backed by Arkouda) could fail unexpectedly. This change restores compatibility without introducing unnecessary data movement.

Testing

• New targeted unit tests added under tests/pandas/extension
• All existing tests continue to pass

Backward Compatibility
This is a strict improvement:

• No API removal
• No behavior change unless pandas previously hit the unimplemented view() path
• No additional copying of Arkouda data

Closes #5344: ArkoudaExtensionArray.view

[codecov]

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Additional details and impacted files

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[1RyanK]

Looks good!

[drculhane]

Looks solid.

[jaketrookman]

Looks good