[draft] Rework applicative options

[mwestphal]

Complete refactoring of the options parsing mechanism in F3D application.

Fixes: https://github.com/f3d-app/f3d/issues/1569

The logic is:

• Parse the CLI once, store the CLI options in a single ConfigDict in a ConfigEntries
• Parse the config file once, store in a ConfigEntries
• Update the app and lib options with config < cli logic without a provided filename
• Finish engine, window initialization
• Create a dynamic config dict containing the changed option and emplace in DynamicConfigEntries
• Update the app and lib options with config < cli < dynamic logic with filename

Devs:

• Create a new F3DCLIOptionsTools namespace that declare all app options and corresponding libf3d options and parse CLI
• Expose F3DConfigFileTools and update the config parsing feature
• Rewrite fully F3DStarter to use F3DCLIOptionsTools and F3DConfigFileTools relying on a clear logic

TODO:

• Adress all todos
• Doc

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 97.72257% with 11 lines in your changes missing coverage. Please review.

Project coverage is 96.82%. Comparing base (6ef173d) to head (0555a6e). Report is 5 commits behind head on master.

Files with missing lines	Patch %	Lines
application/F3DSystemTools.cxx	77.27%	5 Missing :warning:
application/F3DConfigFileTools.cxx	94.33%	3 Missing :warning:
application/F3DOptionsTools.cxx	98.94%	2 Missing :warning:
application/F3DStarter.cxx	99.46%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1580      +/-   ##
==========================================
- Coverage   96.85%   96.82%   -0.04%     
==========================================
  Files         107      108       +1     
  Lines        7694     7643      -51     
==========================================
- Hits         7452     7400      -52     
- Misses        242      243       +1     

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[snoyer]

There has been an issue in the past with cxxopts being too eager to split arguments into vectors; #1078 fixed it with a workaround because cxxopts's splitting was needed for point3/vector3/color arguments. However now that f3d parses vectors itself if would be worth checking if we can disable cxxopts splitting entirely and possibly remove the workaround.

#define CXXOPTS_VECTOR_DELIMITER '\0' would tell cxxopts to split on null and therefore never split.

[mwestphal]

There has been an issue in the past with cxxopts being too eager to split arguments into vectors; #1078 fixed it with a workaround because cxxopts's splitting was needed for point3/vector3/color arguments. However now that f3d parses vectors itself if would be worth checking if we can disable cxxopts splitting entirely and possibly remove the workaround.

#define CXXOPTS_VECTOR_DELIMITER '\0' would tell cxxopts to split on null and therefore never split.

Absolutely correct! --input is back!