the issue is: the text_format widget display wrongly.

• previously before PR#1444, this code using the for loop below to generate the format_string, which MAYBE to prevent showing the S symbol.
• but after PR#1444, the entireh of symfield code not compatible with this design anymore.
• however the encoder_def struct itself has a field called word_format, which exactly be able to use as the format_string,
• because itself is ONLY a hint text, not impact protocol things.
• When you find OOK protocol is broken and see this commit from git blame, please be aware that it's not from here.
• previously me and @cusspvz already found it broken, before 1444 and before this PR. And this commit is just to fix the broken that from PR SymField rewrite #1444.