chore: improve the godoc of all PDF engine packages

pkg/modules/exiftool/doc.go

@@ -1,8 +1,11 @@
 // Package exiftool provides an implementation of the gotenberg.PdfEngine
-// interface using the ExifTool command-line tool. This package allows for reading and
-// writing of metadata, but does not support the merging of PDF files
-// nor conversion to specific PDF formats. The path to the exiftool binary must be
-// specified using the EXIFTOOL_BIN_PATH environment variable.
+// interface using the ExifTool command-line tool. This package allows for:
+//
+// 1. The reading of metadata.
+// 2. The writing of metadata.
+//
+// The path to the exiftool binary must be specified using the
+// EXIFTOOL_BIN_PATH environment variable.
 //
 // See: https://exiftool.org.
 package exiftool

pkg/modules/libreoffice/pdfengine/doc.go

@@ -1,4 +1,6 @@
 // Package pdfengine provides a module which interacts with LibreOffice via the
 // UNO (Universal Network Objects) API and implements the gotenberg.PdfEngine
-// interface.
+// interface. This package allows for:
+//
+// 1. The conversion to specific PDF formats.
 package pdfengine

pkg/modules/pdfcpu/doc.go

@@ -1,6 +1,7 @@
 // Package pdfcpu provides an implementation of the gotenberg.PdfEngine
-// interface using the pdfcpu library. This package allows for the merging of
-// PDF files but does not support conversion to specific PDF formats.
+// interface using the pdfcpu library. This package allows for:
+//
+// 1. The merging of PDF files.
 //
 // See: https://github.com/pdfcpu/pdfcpu.
 package pdfcpu

pkg/modules/pdftk/doc.go

@@ -1,8 +1,10 @@
 // Package pdftk provides an implementation of the gotenberg.PdfEngine
-// interface using the PDFtk command-line tool. This package allows for the
-// merging  of PDF files but does not support conversion to specific PDF
-// formats. The path to the PDFtk binary must be specified using the
-// PDFTK_BIN_PATH environment variable.
+// interface using the PDFtk command-line tool. This package allows for:
+//
+// 1. The merging of PDF files.
+//
+// The path to the PDFtk binary must be specified using the PDFTK_BIN_PATH
+// environment variable.
 //
 // See: https://gitlab.com/pdftk-java/pdftk.
 package pdftk

pkg/modules/qpdf/doc.go

@@ -1,8 +1,10 @@
 // Package qpdf provides an implementation of the gotenberg.PdfEngine
-// interface using the QPDF command-line tool. This package allows for the
-// merging  of PDF files but does not support conversion to specific PDF
-// formats. The path to the QPDF binary must be specified using the
-// QPDK_BIN_PATH environment variable.
+// interface using the QPDF command-line tool. This package allows for:
+//
+// 1. The merging of PDF files.
+//
+// The path to the QPDF binary must be specified using the QPDK_BIN_PATH
+// environment variable.
 //
 // See: https://github.com/qpdf/qpdf.
 package qpdf