Fix PyPDF2 3.0+ compatibility issues

Add compatibility wrapper classes for PdfFileWriter/PdfFileReader
to support both PyPDF2 2.x and 3.x versions.

Changes:
- Add PdfWriter/PdfReader compatibility wrappers in odoo/tools/pdf.py
- Add compatibility classes in odoo/addons/base/models/ir_actions_report.py
- Create comprehensive documentation in doc/PATCH_PDFWRITER.md

Resolves PyPDF2.errors.DeprecationError: PdfFileWriter is deprecated
and was removed in PyPDF2 3.0.0.

🤖 assisted by claude

odoo-bringout-oca-ocb-base/odoo/addons/base/models/ir_actions_report.py

@@ -24,7 +24,33 @@ from lxml import etree
 from contextlib import closing
 from reportlab.graphics.barcode import createBarcodeDrawing
 from reportlab.pdfbase.pdfmetrics import getFont, TypeFace
-from PyPDF2 import PdfFileWriter, PdfFileReader
+try:
+    from PyPDF2 import PdfWriter, PdfReader
+    
+    # Create compatibility classes for old PyPDF2 API
+    class PdfFileWriter(PdfWriter):
+        def addPage(self, page):
+            return self.add_page(page)
+        
+        def addMetadata(self, metadata):
+            return self.add_metadata(metadata)
+        
+        def appendPagesFromReader(self, reader, after_page_append=None):
+            return self.append_pages_from_reader(reader, after_page_append)
+    
+    class PdfFileReader(PdfReader):
+        def getNumPages(self):
+            return len(self.pages)
+        
+        def getPage(self, page_num):
+            return self.pages[page_num]
+        
+        @property
+        def numPages(self):
+            return len(self.pages)
+
+except ImportError:
+    from PyPDF2 import PdfFileWriter, PdfFileReader
 from collections import OrderedDict
 from collections.abc import Iterable
 from PIL import Image, ImageFile