GH-42018: [Python][C++] Arrow sting types conversion to numpy StringDType

[alippai]

Implement the second part of #42018
Complement #48391

Rationale for this change

Faster numpy conversion

What changes are included in this PR?

Arrow string and stringview conversion to numpy StringDType

Are these changes tested?

New tests were added for 4 types and different scenarios

Are there any user-facing changes?

New feature, new python function parameter

• GitHub Issue: [Python] Conversion to/from numpy 2.0+ new StringDType #42018

[github-actions]

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