CI failures were caused by cross-test module identity drift: import-independence property tests cleared aci* entries from sys.modules globally and left later tests comparing objects from different module instances. This manifested as isinstance(...) failures in graph model assertions.

• Root cause addressed: isolate and restore module cache state

  • Updated get_transitive_imports() in:
    • tests/property/test_http_server_independence_properties.py
    • tests/property/test_mcp_server_independence_properties.py
  • New behavior:
    • Snapshot existing aci* modules
    • Clear aci* modules to measure transitive imports from a clean state
    • Restore original aci* modules in finally to avoid leaking interpreter state

• Cleanup for readability/maintainability

  • Added _is_aci_module(name: str) -> bool helper in both files to centralize module-name matching logic.
  • Removed duplicated per-test cache-clearing blocks now handled safely inside the shared helper.

Example of the key change pattern:

aci_modules = {k: v for k, v in sys.modules.items() if _is_aci_module(k)}
for mod in aci_modules:
    del sys.modules[mod]

try:
    __import__(module_name)
    return set(sys.modules) - before_import
finally:
    for mod in [k for k in sys.modules if _is_aci_module(k)]:
        del sys.modules[mod]
    sys.modules.update(aci_modules)