OpenSystemsDevelopment / qpdf

…`warn`, streamline condition handling.

… warnings, and centralize utility methods.

Refactor `ImageOptimizer`: enforce `final` overrides, switch to `uniq…

… pipelines and simplify conditions.

Refactor `ResourceFinder`: streamline logic and optimize data structu…

Allow null `callbacks` in content stream handling

Introduce null checks for `callbacks` in `QPDFObjectHandle` to allow content streams to be parsed without ParserCallbacks. Update `QPDFJob` to pass `nullptr` instead of `DiscardContents` for parsing.

Disallow `--deterministic-id` with encrypted output and improve error…

…or deterministic ID generation (fixes #1235).

Refactor `validatePDFVersion` and `findHeader`: simplify logic, impro…

…ity, and replace deprecated API usage.

Refactor `QPDF::calculateHPageOffset`: simplify loops with range-base…

…ace manual index handling, revise min/max initialization to use `std::numeric_limits`, and optimize shared identifier assignments.

Refactor QPDF::ObjUser

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

…r,  and revise enum initialization. Clean up unused error handling in linearization logic.

Update `unparseChild` and `unparseObject` in `QPDFWriter` to use `siz…

…evel` and add `const&` to `child` parameter.

Improve linearization logic to handle invalid thumbnails gracefully a…

…bnail processing loop to ensure consistency.

Fix linearization logic to conditionally add outlines object only if …

…uring robustness against damaged PDFs.

Enhance `QPDF_objects` to ignore excessively large object stream IDs …

…eams, improving robustness against damaged PDFs.

Refactor Pl_Base64

Enhance `QPDFParser` sanity checks after xref recovery to include par…

…oding/decoding logic, and simplify usage in `JSON_writer` and `QPDF_json`.

…view` for encoding/decoding, improving memory efficiency and simplifying buffer management

…e` and `finish` logic

…cing buffered reads with direct data extraction from `InputSource`.

Refactor `NNTree` to encapsulate warning and error handling

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

Add check for shared appearance stream in QPDFFormFieldObjectHelper

Ensure an appearance stream is not shared  before generating text appearances, improving error handling and data integrity.

Refactor is::OffsetBuffer and BufferInputSource

…string`, improving performance, simplifying stream data handling, and reducing dependency on `BufferInputSource`.

…std::string_view`, improving performance and code clarity.