Add regression test for static field from missing class

[tautschnig]

Add a regression test verifying that static fields accessed via getstatic bytecode from a missing class are properly marked with is_static_lifetime and nondet-initialized. The underlying issue was already fixed by the create_stub_global_symbol function (commit e163ab6, Feb 2018), which correctly sets is_static_lifetime=true for stub globals. This test guards against regressions.

Fixes: #851

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[Copilot]

Pull request overview

Adds a new JBMC regression test intended to guard against regressions where a getstatic access to a static field of a missing class fails to create a proper stub global (with is_static_lifetime set) and fails to nondet-initialize it.

Changes:

• Add a new regression directory static_field_missing_class/ with a minimal Java program that reads a static field from a missing class.
• Add a test.desc expecting an assertion failure and a warning.
• Check in the precompiled a.class artifact for the regression.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
jbmc/regression/jbmc/static_field_missing_class/test.desc	Adds a regression harness entry to run JBMC and match expected output.
jbmc/regression/jbmc/static_field_missing_class/a.java	Adds the Java source corresponding to the test scenario (missing class static field access).
jbmc/regression/jbmc/static_field_missing_class/a.class	Adds the compiled bytecode used by the regression test.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.41%. Comparing base (85c204f) to head (eabdff5).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8762   +/-   ##
========================================
  Coverage    80.41%   80.41%           
========================================
  Files         1703     1703           
  Lines       188398   188398           
  Branches        73       73           
========================================
+ Hits        151498   151499    +1     
+ Misses       36900    36899    -1     

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