CLN: Refactor np_can_hold_element to reduce cyclomatic complexity
### Overview

This PR refactors the `np_can_hold_element` function to reduce its cyclomatic complexity and improve maintainability. The function was decomposed into smaller helper functions (`_handle_integer_dtype`, `_handle_float_dtype`, etc.), each handling a specific dtype logic. This improves readability and reduces the complexity of the main function.

### Changes

- Refactored `np_can_hold_element` into smaller helper functions:
  - `_handle_integer_dtype`
  - `_handle_float_dtype`
  - `_handle_complex_dtype`
  - `_handle_boolean_dtype`
  - `_handle_string_dtype`
- Added docstrings to the helper functions for better documentation.
- Ensured no changes to functionality or behavior during the refactor.
- Ran `flake8` and fixed style issues to comply with the project's code standards.

### Testing

- Verified that all existing tests in the Pandas test suite pass.
- Confirmed no behavioral changes in `np_can_hold_element`.

### Notes for Reviewers

- The refactor was aimed at maintainability; the logic remains consistent with the original implementation.
- Suggestions for additional tests or improvements are welcome.
was in pandas/core/dtypes/cast.py:
![image](https://github.com/user-attachments/assets/e7800ea2-7f9e-47c1-857c-1dfc96bfacda)
now in pandas/core/dtypes/cast.py:
![image](https://github.com/user-attachments/assets/2e27030c-490a-4479-8298-3d751a953d04)
 Thanks for the effort here but the project doesn't enforce any standards with regards to complexity so I don't think this refactor is worthwhile. Going to close but happy to have contributes toward issues labeled `good first issue`