feat: Enhance speaker analysis with gender inference and update related tests

tests/conftest.py

@@ -0,0 +1,13 @@
+import importlib
+import sys
+
+# Ensure real optional dependencies are imported before tests that install stubs
+# so that available packages (like ebooklib, bs4) aren't replaced with dummy modules.
+for module_name in ("ebooklib", "bs4"):
+    if module_name not in sys.modules:
+        try:
+            importlib.import_module(module_name)
+        except Exception:
+            # On environments without the optional dependency, downstream tests
+            # will install lightweight stubs as needed.
+            pass