Simplified struct field handling in the WASM bindings

PiperOrigin-RevId: 829003969
Change-Id: I139f9c0dad96e1664b1bd054f09fcdf58aff260e

wasm/codegen/helpers/common.py

@@ -61,11 +61,14 @@ def write_to_file(filepath: str, content: str) -> None:
     print(f"Error writing to output file: {filepath} - {e}")
 
 
+def lowercase_first_letter(input_string: str) -> str:
+  """Lowercases the first letter of a string."""
+  return input_string[:1].lower() + input_string[1:]
+
+
 def uppercase_first_letter(input_string: str) -> str:
   """Uppercases the first letter of a string."""
-  if input_string:
-    return input_string[0].upper() + input_string[1:]
-  return input_string
+  return input_string[:1].upper() + input_string[1:]
 
 
 def try_cast_to_scalar_type(value: str) -> int | float | str: