fix: use 'Solution' instead of 'Solution to' when exercise_style is set

When exercise_style='solution_follow_exercise', the solution title
should be just 'Solution' not 'Solution to'. This fix updates the
directive to use the correct default title text based on the config.

- Update SolutionDirective to check exercise_style config
- Set title_text to 'Solution' when config is set
- Keep 'Solution to' for default behavior
- Update tests to expect correct 'Solution' title

Author: mmcky

sphinx_exercise/directive.py

@@ -222,7 +222,11 @@ class : str,
     solution_node = solution_node
 
     def run(self) -> List[Node]:
-        self.defaults = {"title_text": f"{translate('Solution to')}"}
+        # Set default title based on exercise_style config
+        if self.env.app.config.exercise_style == "solution_follow_exercise":
+            self.defaults = {"title_text": f"{translate('Solution')}"}
+        else:
+            self.defaults = {"title_text": f"{translate('Solution to')}"}
         target_label = self.arguments[0]
         self.serial_number = self.env.new_serialno()
 

tests/test_exercise_style.py

@@ -38,8 +38,8 @@ def test_solution_no_link(app):
     # Check that the title is just "Solution" without exercise reference
     title_text = title.get_text()
     assert (
-        title_text.strip() == "Solution to"
-    ), "Solution title should be just 'Solution to' when exercise_style='solution_follow_exercise'"
+        title_text.strip() == "Solution"
+    ), "Solution title should be just 'Solution' when exercise_style='solution_follow_exercise'"
 
 
 @pytest.mark.sphinx("html", testroot="mybook", confoverrides={"exercise_style": ""})
@@ -97,5 +97,5 @@ def test_solution_no_link_unenum(app):
     # Check that the title is just "Solution" without exercise reference
     title_text = title.get_text()
     assert (
-        title_text.strip() == "Solution to"
-    ), "Solution title should be just 'Solution to' when exercise_style='solution_follow_exercise'"
+        title_text.strip() == "Solution"
+    ), "Solution title should be just 'Solution' when exercise_style='solution_follow_exercise'"