GH-20125: [Docs][Python] Restructure developers/python.rst (#47334)

### Rationale for this change
The structure of the Python build and development documentation has become unclear due to multiple incremental changes over time. This PR aims to improve clarity and organization.

### What changes are included in this PR?
- Introduces tabs to improve navigation.
- Splits the existing documentation into two focused pages: Building and Developing PyArrow.

### Are these changes tested?
Yes. With docs preview build.

### Are there any user-facing changes?
No. Only docs changes.

* GitHub Issue: #20125

Authored-by: AlenkaF <[email protected]>
Signed-off-by: Raúl Cumplido <[email protected]>

Author: AlenkaF

docs/source/developers/guide/step_by_step/building.rst

@@ -142,10 +142,6 @@ Building other Arrow libraries
 
          - :ref:`build_pyarrow`
 
-         Or
-
-         - :ref:`build_pyarrow_win`
-
       When you will make change to the code, you may need to recompile
       PyArrow or Arrow C++:
 

docs/source/developers/index.rst

@@ -39,6 +39,8 @@ Connection to the specific language development pages:
    .. tab-item:: Python
 
       * :ref:`python-development`
+      * :ref:`build_pyarrow`
+      * :ref:`develop_pyarrow`
 
    .. tab-item:: R
 
@@ -228,7 +230,7 @@ All participation in the Apache Arrow project is governed by the ASF's
    reviewing
    cpp/index
    java/index
-   python
+   python/index
    continuous_integration/index
    benchmarks
    documentation