OpenSystemsDevelopment / qpdf

…gin`/`end` methods, update calls across codebase, and streamline page handling logic.

…` to `Pages`, update methods to use relocated fields, and streamline cache handling.

… to improve code organization.

… streamline error handling, and improve encapsulation.

Encapsulate linearization-related logic in `QPDF::Doc::Linearization`. Refactor methods, relocate implementations, and update all references accordingly to streamline and centralize linearization functionality.

Relocate `Pages` methods to `QPDF::Doc` for improved encapsulation of page-related logic. Adjust all references and methods to use the new placement.

Streamline `setLastObjectDescription` usage by consolidating string construction at call sites. Relocate method to the private section to improve encapsulation and restrict access.

Relocate `Objects` to `QPDF::Doc` for improved encapsulation of object-related logic. Adjust all relevant methods and references to use the new placement.

…directives across modules to improve clarity and enforce better assertion practices.

… numbers and related variables, replacing `int`, to enhance consistency and avoid unnecessary checked conversions.

Modernise constructors, make classes final, etc.

This improves indentation of long strings. This commit also fixes some
trailing whitespace in ChangeLog.

This reverts commit ff2a78f579ebdd06b417e34260a17dba06e71137, reversing
changes made to 8f54319f7a6514110f4b05cbbf1cb1c9fc8cb6a0.

This reverts commit c648b9a018105a3c30b3e7f3c5f8a058d3ddd92c, reversing
changes made to 12b67a3227df6b6df3a4f5f098e11cce173ff7d5.

Add fuzz case 68377.

Using search and replace.

Add new convenience class QPDFObjGen::Guard

Remove unnecessary parameters.
Remove code that is unnecessary as result of a prior call to QPDF::getAllPages.
Avoid clearing and rebuilding of m->all_pages.

Change method signatures to use QPDFObjGen.
Use QPDFObjGen methods where possible.
Remove redundant QPDF::objGenToIndirect.