Merge feature/fix-ci-node24: CI fixes — simplify test step, Node.js 24, SyntaxWarning

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: daviddesancho

.github/workflows/ci.yml

@@ -6,6 +6,9 @@ on:
   pull_request:
     branches: [master, develop]
 
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
 jobs:
   test:
     name: Python ${{ matrix.python-version }} / ${{ matrix.os }}
@@ -45,8 +48,4 @@ jobs:
         run: conda list | grep -E "numpy|scipy|mdtraj|networkx|scikit"
 
       - name: Run tests
-        run: |
-          pytest mastermsm/test/ -v --tb=long > pytest-output.txt 2>&1
-          RESULT=$?
-          cat pytest-output.txt
-          exit $RESULT
+        run: pytest mastermsm/test/ -v --tb=long

mastermsm/fewsm/fewsm.py

@@ -65,9 +65,9 @@ def eigen_group(self, N=2, method="robust"):
         keep_states = self.parent.keep_states
         macros[0] = list(range(len(keep_states)))
         for n in range(1, N):
-            if method is "robust":
+            if method == "robust":
                 macro_new, _ = fewsm_lib.split_sigma(macros, lvecs[:,n])
-            elif method is "sign":
+            elif method == "sign":
                 macro_new, _ = fewsm_lib.split_sign(macros, lvecs[:,n])
             macros = copy.deepcopy(macro_new)
         print ("\n Initial membership of microstates to macrostates:")