Add comprehensive test suite with 133 tests

[santiagocasas]

• Add tests for fishconsumer module (25 tests)
• Add tests for config module (15 tests)
• Add tests for utils module (24 tests)
• Add tests for legendre_tools module (11 tests, 100% coverage)
• Add tests for colors module (17 tests, 100% coverage)
• Add tests for likelihood base module (9 tests)
• Improved overall test coverage from ~30% to 48%
• All 133 tests passing with comprehensive validation
• Includes mock-based testing for complex dependencies
• Fast execution tests focused on functionality validation

Fixes #

Changes proposed in this pull request:

Before submitting

• I've read and followed all steps in the Making a pull request
  section of the CONTRIBUTING docs.
• I've updated or added any relevant docstrings following the syntax described in the
  Writing docstrings section of the CONTRIBUTING docs.
• If this PR fixes a bug, I've added a test that will fail without my fix.
• If this PR adds a new feature, I've added tests that sufficiently cover my new functionality.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.44%. Comparing base (ddeeed7) to head (6b6869d).
⚠️ Report is 26 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #152       +/-   ##
===========================================
+ Coverage   46.35%   56.44%   +10.09%     
===========================================
  Files          34       34               
  Lines        5993     5993               
===========================================
+ Hits         2778     3383      +605     
+ Misses       3215     2610      -605     

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[Copilot]

Pull Request Overview

This pull request adds a comprehensive test suite to significantly improve the test coverage of the cosmicfishpie project, expanding from approximately 30% to 48% coverage with 133 new tests across 6 key modules.

• Adds extensive test coverage for utility modules (utils, legendre_tools, colors) with validation of mathematical operations and helper functions
• Implements configuration and likelihood testing with mock-based approaches to handle complex dependencies
• Provides thorough coverage of analysis utilities including color formatting and ANSI terminal output functions

Reviewed Changes

Copilot reviewed 5 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/utils_test.py	Comprehensive testing of utility classes including deepupdate, debug printing, numerical operations, and filesystem helpers
tests/likelihood_base_test.py	Basic test coverage for likelihood module with defensive imports and error handling for missing functions
tests/legendre_tools_test.py	Complete testing of Legendre polynomial tools and Wigner matrices with mathematical validation
tests/config_test.py	Configuration module testing with mocked dependencies and YAML operations validation
tests/colors_test.py	Full coverage of color utility functions including ANSI terminal formatting and RGB color generation

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[Sefa76]

LGTM