Resolve invalid keys to KC.NO instead of ValueError

kmk/modules/holdtap.py

@@ -54,7 +54,7 @@ class HoldTap(Module):
     def __init__(self):
         self.key_buffer = []
         self.key_states = {}
-        if not KC.get('HT'):
+        if KC.get('HT') == KC.NO:
             make_argumented_key(
                 validator=HoldTapKeyMeta,
                 names=('HT',),

kmk/modules/string_substitution.py

@@ -42,12 +42,11 @@ class Phrase:
         self._characters: list[Character] = []
         self._index: int = 0
         for char in string:
-            try:
-                key_code = KC[char]
-                shifted = char.isupper() or key_code.has_modifiers == {2}
-                self._characters.append(Character(key_code, shifted))
-            except ValueError:
+            key_code = KC[char]
+            if key_code == KC.NO:
                 raise ValueError(f'Invalid character in dictionary: {char}')
+            shifted = char.isupper() or key_code.has_modifiers == {2}
+            self._characters.append(Character(key_code, shifted))
 
     def next_character(self) -> None:
         '''Increment the current index for this phrase'''