OpenSystemsDevelopment / qpdf

…y` with subscript operator, and simplify logic.

…`getKey` with subscript operator, and simplify logic.

…ictionary` APIs, replace `getKey` with subscript operator, streamline logic, and simplify bounds checks.

- Marked `NNTreeIterator` and `NNTreeImpl` as `final` to prevent inheritance.
- Inlined `NNTreeIterator` and `NNTreeImpl` methods to streamline code and reduce redundancy.
- Updated constructors, operators, and utility functions in `NNTreeIterator` and `NNTreeImpl` for improved readability and maintainability.

- Added `const` qualifiers to member functions and parameters where applicable.
- Replaced `QPDFObjectHandle` arrays with `qpdf::Array` for improved type clarity.
- Simplified logic in `compareKeyItem` and `compareKeyKid` by removing redundant checks.

- Simplified the code by directly handling limits validation in `compareKeyKid`.
- Improved clarity by reducing unnecessary method indirection.

- Removed `NNTreeDetails` and moved key validation logic directly into `NNTreeImpl`.
- Replaced type determination with `qpdf_object_type_e` for improved clarity.
- Updated `QPDFNameTreeObjectHelper` and `QPDFNumberTreeObjectHelper` to align with the new `NNTreeImpl` structure.
- Simplified methods accessing tree items and validating keys.

- Introduced a `validate()` method in `QPDFNameTreeObjectHelper`, `QPDFNumberTreeObjectHelper`, and `NNTreeImpl`.
- Ensure proper validation of tree keys and values, detecting invalid entries, unsorted keys, and inconsistencies.
- Added support for auto-repair in case of validation errors.

- Introduced `std::function<bool(QPDFObjectHandle const&)>` to validate tree values.
- Updated constructors and methods across `QPDFNameTreeObjectHelper` and `QPDFNumberTreeObjectHelper` to support value validation.
- Refactored `NNTreeImpl` to check for invalid values during insertion, iteration, and retrieval.
- Improved error handling and reporting for invalid values.

…eplace `getArrayNItems` with `size`, and improve error handling logic.

…lify `withinLimits` logic, and improve code readability with subscript operators.

…edundant debug traces.

…and improve `findInternal` readability.

…dding error counting and leveraging `reconstructed_xref` for improved robustness, limiting the acceptable number of errors for damaged files.

Refactored several classes to use C++11 `final` specifiers for inheritance restrictions and added default member initializations. These changes enhance code clarity, improve safety, and ensure modern coding practices.

Remove the name/number tree object helper constructors that don't take
a QPDF&.

Run this:

for i in  **/*.cc **/*.c **/*.h **/*.hh; do
  clang-format < $i >| $i.new && mv $i.new $i
done

Create the typedefs directly in iterators rather than deriving from
the deprecated std::iterator class.

Keep a std::pair internal to the iterators so that operator* can
return a reference and operator-> can work, and each can work without
copying pairs of objects around.

Add constructors that take a QPDF object so we can issue warnings and
create new indirect objects.

Create a computationally and memory efficient implementation of name
and number trees that does binary searches as intended by the data
structure rather than loading into a map, which can use a great deal
of memory and can be very slow.