fix(naming): correct language tag rule matching and add state conditions

Rules took only a scalar, so the documented list syntax raised LanguageTagError after the mux. Normalise every condition, treat an invalid tag as no match, guard the surrounding post-mux config reads, and let a rule match dual, multi and dubbed so a release can carry its own tag.

tests/core/test_dual_multi_naming.py

@@ -118,3 +118,10 @@ def test_count_never_dubbed(count_mode):
     assert c["dubbed"] == ""
     assert c["dual"] == ""
     assert c["multi"] == ""
+
+
+def test_a_missing_template_key_falls_back_instead_of_raising(monkeypatch):
+    """dl only checks output_template is non-empty, so the title's own key can be absent."""
+    monkeypatch.setattr(config, "output_template", {"series": "{title}"})
+    name = make_movie("en").get_filename(make_media_info(["en"]))
+    assert name == "The Film (2024)"