Improve build_model tests to fail on errors

[bernalde]

Summary

• ensure unexpected errors in build_model tests cause test failures
• apply the same logic to remaining tests that construct models
• skip tests when external solvers are missing
• consolidate model-specific construction tests into one parametrized check
• expand model construction checks to all modules instead of just cstr, biofuel and gdp_col

Testing

• pytest -k module_imports -q
• pytest -k model_construction -q

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https://chatgpt.com/codex/tasks/task_b_6886fb5034388327a85683b7420a509d