Add DbfWriter and refactor Writer to use it

REfactor dbf writing logic into DbfWriter.  Make property wrappers of shp, shx and dbf instead of __getFileObj.

Passes mypy and Pytest

Remove typing.Never.  Ruff check and format

Add setter for Writer.fields

Author: JamesParrott

README.md

@@ -8,7 +8,7 @@ The Python Shapefile Library (PyShp) reads and writes ESRI Shapefiles in pure Py
 
 - **Author**: [Joel Lawhead](https://github.com/GeospatialPython)
 - **Maintainers**: [James Parrott](https://github.com/JamesParrott) & [Karim Bahgat](https://github.com/karimbahgat)
-- **Version**: 3.0.7
+- **Version**: 3.0.8
 - **Date**: 20th May 2026
 - **License**: [MIT](https://github.com/GeospatialPython/pyshp/blob/master/LICENSE.TXT)
 
@@ -93,6 +93,11 @@ part of your geospatial project.
 
 # Version Changes
 
+## 3.0.8
+
+### Testability / separation of concerns.
+ - Separate dbf only writing methods into a new dbfWriter class (an instance of which is owned by the regular Shapefile Writer class).
+
 ## 3.0.7
 
 ### Testability / separation of concerns.

changelog.txt

@@ -1,3 +1,9 @@
+VERSION 3.0.8
+
+2026-05-20
+	Testability / separation of concerns:
+	* Separate dbf only writing methods into a new dbfWriter class (an instance of which is owned by the regular Shapefile Writer class).
+
 VERSION 3.0.7
 
 2026-05-20