tests/docs: unique-name driver loading; moving-path lifecycle and settings notes; VIV predeclare renamed

Tests load research drivers via importlib under unique module names
instead of a bare 'import run' (shared-process collision between the
Dütsch and VIV drivers). lifecycle.md qualifies immutable geometry and the
host-only get_flags for translating circles; supported_settings.md points to
the dense-only moving-circle feature; leontini_viv_predeclare.md is renamed
viv_re150_predeclare.md (Re 150 Kolahdouz/Qin case) with references updated.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/unit/test_viv_logic.py

@@ -8,6 +8,20 @@ _spec = importlib.util.spec_from_file_location(
 viv = importlib.util.module_from_spec(_spec)
 _spec.loader.exec_module(viv)
 
+def _load(rel, name):
+    """Load a research driver module under a unique name (no bare ``import run``)."""
+    import sys
+    path = Path(__file__).resolve().parents[2] / rel
+    sys.path.insert(0, str(path.parent))  # for the driver's own sibling imports
+    try:
+        spec = importlib.util.spec_from_file_location(name, path)
+        mod = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(mod)
+    finally:
+        sys.path.remove(str(path.parent))
+    return mod
+
+
 D, U = 40, 0.04
 
 
@@ -72,12 +86,7 @@ def test_seed_reset_discards_incomplete_cycle_and_proof():
 
 def test_viv_config_passes_the_real_loader(tmp_path):
     import json
-    import sys
-    sys.path.insert(0, str(Path(__file__).resolve().parents[2] / "research/viv_re150"))
-    try:
-        import run
-    finally:
-        sys.path.pop(0)
+    run = _load("research/viv_re150/run.py", "viv_run")
     from CelerisLab.config import load_lbm_config
     cfg_dict, nx, ny = run.config()
     path = tmp_path / "config_lbm.json"