esp32-build: robustness - ignore codeword payload with bad length word

Author: Jamie C. Driver

src/bytewords.cpp

@@ -64,9 +64,13 @@ static const int16_t _lookup[] = {
 };
 
 static bool decode_word(const string& word, size_t word_len, uint8_t& output) {
-    assert(word.length() == word_len);
     const size_t dim = 26;
 
+    // Sanity check
+    if(word.length() != word_len) {
+        return false;
+    }
+
     // If the coordinates generated by the first and last letters are out of bounds,
     // or the lookup table contains -1 at the coordinates, then the word is not valid.
     int x = tolower(word[0]) - 'a';