Add unit tests to increase coverage

[vissarion]

Add 7 new test files with 130+ test cases covering previously untested code:

• poset_misc_test.cpp: Poset class (verify, constructor, is_in, topology sort) and misc.h utilities (read_pointset, read_objective, read_poset_from_file)
• generators_test.cpp: All known polytope generators (cube, cross, simplex, prod_simplex, skinny_cube, birkhoff) in H and V representations
• convex_body_test.cpp: ConvexBody class and unit ball generators
• zonotope_gen_test.cpp: Random zonotope generators (gaussian, uniform, exponential)
• small_utils_test.cpp: Combined tests for known generators and convex body
• print_table_test.cpp: VariadicTable printing utility
• sdpa_format_test.cpp: SDPA file format read/write/roundtrip

Add coverage job to cmake-gcc workflow (lcov-based, runs on PRs).

[Copilot]

Pull request overview

This pull request adds several new doctest-based C++ unit test executables to increase coverage across generators, convex bodies, poset/misc utilities, SDPA format IO, and a table-printing utility, and introduces a GCC-based coverage job in CI.

Changes:

• Added new unit test source files covering zonotope/polytope generators, ConvexBody behavior, Poset + misc parsing utilities, SDPA read/write roundtrips, and VariadicTable output.
• Wired the new tests into test/CMakeLists.txt via new add_executable()/add_test() entries.
• Added a new lcov-based “Coverage (gcc)” job to the cmake-gcc GitHub Actions workflow.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
test/zonotope_gen_test.cpp	Adds basic checks for random zonotope generators and seed reproducibility.
test/small_utils_test.cpp	Adds compact tests for known generators, convex body generators, and an extra poset scenario.
test/sdpa_format_test.cpp	Adds SDPA read/write and roundtrip tests, including comment-lines and block-structure cases.
test/print_table_test.cpp	Adds output-based tests for VariadicTable formatting options.
test/poset_misc_test.cpp	Adds extensive unit tests for Poset plus misc parsing helpers (read_*).
test/generators_test.cpp	Adds broader coverage for known polytope generators and basic geometric assertions.
test/convex_body_test.cpp	Adds behavior tests for unit ball generators and intersection/search helpers.
test/CMakeLists.txt	Registers new test executables and ctest entries for the added test files.
.github/workflows/cmake-gcc.yml	Adds a new coverage job intended to run on PRs using lcov.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 6 comments.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 6.35%. Comparing base (32e3421) to head (d420471).
⚠️ Report is 31 commits behind head on develop.

❗ There is a different number of reports uploaded between BASE (32e3421) and HEAD (d420471). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (32e3421)	HEAD (d420471)
	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #494       +/-   ##
===========================================
- Coverage    57.28%   6.35%   -50.93%     
===========================================
  Files          114     116        +2     
  Lines         7241    7392      +151     
  Branches      3239    3468      +229     
===========================================
- Hits          4148     470     -3678     
- Misses         976    6555     +5579     
+ Partials      2117     367     -1750     

Flag	Coverage Δ
unittests	6.35% <ø> (?)

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see 113 files with indirect coverage changes

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