Version 2.7.2: Faster compiles

This patch release makes the precompiled and experimental module modes cheaper
for clients. Include-what-you-use is followed, more function bodies compile into
the library instead of into every translation unit, and the C++20 named module
now imports the precompiled implementation instead of the full header-only
library. It also fixes the Bazel precompiled build, which could give consumers
duplicate implementations.

Changed

• The C++20 named module uses the precompiled implementation and we lowered its
  floor from C++23 to C++20. CLI11::Module now works for both find_package
  and add_subdirectory, and configure fails with a clear message if CMake is
  older than 3.28. #1413
• Removed <iostream>, <codecvt>, <iomanip>, <fstream>, and <locale>
  from the declaration headers, so precompiled clients do not parse them.
  App::exit() is now three overloads instead of one with stream default
  arguments. #1411
• Moved the remaining non-template function bodies out of App.hpp,
  Option.hpp, Validators.hpp, TypeTools.hpp, ConfigFwd.hpp, and
  FormatterFwd.hpp into the impl/*_inl.hpp files, so they compile into the
  library in precompiled mode. Header-only mode is unchanged. #1415
  #1416 #1417

Fixed

• Fixed the Bazel precompiled build: CLI11_COMPILE and
  CLI11_ENABLE_EXTRA_VALIDATORS now propagate to consumers, which previously
  got duplicate implementations from both the headers and the library. Added a
  cli11_header_only target, the Windows shell32 link, and more tests.
  #1420
• Made ExtraValidators_inl.hpp use the same CLI11_ENABLE_EXTRA_VALIDATORS
  test as its header, and gave the file permission validators the
  CLI11_MODULE_INLINE marker the other global validators have. #1415

Documentation

• Documented the precompiled mode in the README. #1412
• Added a minimal module example, corrected the CLI11::Module target name in
  the book, and noted that macros such as CLI11_PARSE do not come through an
  import. #1413

Internal

• Added an iwyu preset that runs include-what-you-use over the one precompiled
  translation unit, with a mapping file for both standard libraries, and applied
  its findings. #1418

Version 2.7.1: LTO link fix

This patch release fixes linking against the precompiled shared library when it
is built with link-time optimization.

Fixed

• Fixed missing symbols in the precompiled library under LTO: Precompile.cpp
  now explicitly instantiates Option::ignore_case<App> and
  ignore_underscore<App>, and the library always compiles the full validator
  set unless CMake disables it. #1409

Documentation

• Added the changelog to the Doxygen site. #1405
• Titled the changelog entries and named the releases from them. #1406

Internal

• Moved the release checklist to a prepare-release skill. #1407

v2.7.0

This version adds a FileSize validator, a PositionalOnly prefix command
mode, and more control over config file generation. It also contains a large set
of bug fixes from a systematic audit of the parsing, config, help formatting,
string handling, and type conversion code, along with performance improvements
that remove unnecessary copies in hot paths.

Added

• Added a FileSize validator to check minimum and maximum file sizes.
  #1305
• Added PrefixCommandMode::PositionalOnly, which restores the pre-2.6.2 prefix
  command behavior as an opt-in mode: only a positional argument or the --
  separator triggers prefix mode, and unrecognized options are collected as
  extras. #1382
• Added an option to write only the active subcommand defaults when generating a
  config file. #1314

Changed

• Improved performance by removing unnecessary string and container copies in
  parsing and validator hot paths. #1368
• Improved the performance of string splitting by replacing a stringstream
  with a find-based loop. #1396
• Sorted the excludes and needs sets by name for stable help output.
  #1308
• Removed en_US.UTF-8 from the unicode locale fallback list. #1312
• Modernization and portability fixes: added missing standard includes, exported
  CLI::Number from the C++20 module, and cleaned up the warning lists.
  #1367
• Aligned the Meson build with wrapdb policy by removing disable_auto_if for
  subprojects. #1349

Fixed

• Fixed require_subcommand maximum enforcement for dot notation and for
  disabled fallthrough, dot-notation subcommands with Windows-style prefixes,
  get_options const/non-const consistency, and a crash when parsing with
  argc == 0. #1363, #1384
• Fixed missing symbol export from the precompiled shared library on macOS.
  #1387
• Fixed double indentation of nested option groups in help output. #1371,
  #1379
• Fixed config reading and writing bugs: section headers with trailing comments,
  one-line multiline comments, embedded delimiters with the Join policy, and
  multiline values for indented keys. #1369, #1361
• Fixed help formatting issues: hidden positionals appearing in the usage line,
  long subcommand names running into their descriptions, and ExtrasError
  reporting the wrong error name. #1369
• Fixed ignore_case and ignore_underscore so both apply when used together.
  #1358
• Fixed string handling edge cases in split_up, remove_quotes,
  append_codepoint, and escape_detect. #1364
• Fixed type conversion edge cases: negative input to unsigned types,
  whitespace-only floating point input, containers of pairs with an odd element
  count, large integer sums, and the Join policy with default values.
  #1362
• Fixed stale processed values being returned after Option::clear(). #1360
• Fixed out-of-bounds reads in the non-codecvt narrow/widen conversion paths
  used under C++26. #1359
• Fixed infinite recursion on subcommand option groups with fallthrough enabled.
  #1316
• Fixed empty strings given to wrapper types such as std::optional to
  consistently produce a default-constructed value. #1340
• Fixed CLI::ExistingFile to reject an empty filename with a clear error.
  #1351
• Fixed an empty description on a modified Transformer. #1345
• Fixed unsigned wraparound in split_program_name for command lines without
  spaces. #1339
• Fixed FileOnDefaultPath with an empty default path, and PositiveNumber
  rejecting subnormal values. #1366
• Fixed compilation with libc++/clang in C++26 mode. #1326
• Fixed the case of the shell32 library name in CMake. #1347
• Removed the static keyword from the precompiled library definition in CMake.
  #1304

Documentation

• Clarified the behavior of the prefix_command overloads. #1310
• Documented the Catch2 dependency for the test build. #1342
• Corrected documentation errors, including the AsSizeValue example, the
  App::required() doc, and validator comments. #1304, #1366
• Modernized some documentation. #1336
• Moved the tutorial book into the Doxygen documentation, modernized the HTML
  output with doxygen-awesome-css, and reorganized the sidebar navigation.
  #1390, #1392, #1397, #1398
• Corrected errors found in a documentation review. #1394
• Split the documentation into Guide and Examples sections and filled gaps in
  the guide. #1400

Internal

• Added a dev CMake preset and workflow for faster local iteration using the
  precompiled library and ccache. #1387
• Added a CUDA test for the single-header build. #1381
• Refactored the duplicated parse-completion pipeline and removed dead code.
  #1365
• Moved static std::string reference initializers to helper functions.
  #1335
• Routed formatter label fallback through an internal helper as a step toward
  internationalization support. #1320
• Cleaned up the CMake logic for finding Catch2 and Boost, and corrected the
  example test regular expressions. #1325, #1322
• Reorganized the GitHub workflows and reduced CI build times. #1323,
  #1387
• Added C++26 CI coverage (GCC, and clang with modules), and made codecov wait
  for all coverage uploads. #1388, #1391
• Tidied the configuration files in the root directory. #1393
• Attached the source packages to tagged releases, wrote the release notes from
  the changelog, and added a CI check for a changelog entry on every build.
  #1401, #1402, #1403

v2.6.2

update changelog for version 2.6.2 (#1297)

update changelog and readme for release 2.6.2

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Henry Schreiner <henry.fredrick.schreiner@cern.ch>

v2.6.1

code simplification (#1244)

Based on #1242, I don't think this is required but it does remove that
issue and checking on compiler explore it does simplify the generated
code.

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

v2.6.0

Version update (#1219)

update changelog for 2.6 release

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

v2.5.0

update version and changelog for 2.5 release (#1121)

update readme, changelog, and version for 2.5 release

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Henry Schreiner <HenrySchreinerIII@gmail.com>

v2.4.2

chore: prepare version 2.4.2 (#1037)

Prepare for release.

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Philip Top <phlptp@gmail.com>

v2.4.1

chore: prepare for 2.4.1 (#1001)

Quick release fixing the missing header.

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Philip Top <phlptp@gmail.com>

v2.4.0

docs: release update (#974)

Update the Readme and the changelog in preparation for a release.

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Henry Schreiner <henry.fredrick.schreiner@cern.ch>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>