fix: map openCharacterDictionary session action to --open-character-dict

- Add missing Lua CLI dispatch entry for openCharacterDictionary
- Add regression test for Alt+Meta+A binding and CLI flag forwarding

scripts/test-plugin-session-bindings.lua

@@ -79,6 +79,14 @@ local ctx = {
 						actionType = "session-action",
 						actionId = "playNextSubtitle",
 					},
+					{
+						key = {
+							code = "KeyA",
+							modifiers = { "alt", "meta" },
+						},
+						actionType = "session-action",
+						actionId = "openCharacterDictionary",
+					},
 					{
 						key = {
 							code = "KeyL",
@@ -153,6 +161,23 @@ local play_next_call = recorded.async_calls[#recorded.async_calls]
 assert_true(play_next_call ~= nil, "play-next binding should invoke CLI action")
 assert_true(play_next_call[2] == "--play-next-subtitle", "play-next binding should pass CLI flag")
 
+local character_dictionary = nil
+for _, binding in ipairs(recorded.bindings) do
+	if binding.keys == "Alt+Meta+a" then
+		character_dictionary = binding
+		break
+	end
+end
+assert_true(character_dictionary ~= nil, "character dictionary binding should be registered")
+
+character_dictionary.fn()
+local character_dictionary_call = recorded.async_calls[#recorded.async_calls]
+assert_true(character_dictionary_call ~= nil, "character dictionary binding should invoke CLI action")
+assert_true(
+	character_dictionary_call[2] == "--open-character-dictionary",
+	"character dictionary binding should pass CLI flag"
+)
+
 starter.fn()
 
 local modified_digit = nil