Maybe a fork of some wiki application can act as a digital townhall library? They usually publish meeting notes on their websites, so why not on a wiki platform, many of them have discussion pages and you could add open sections for public suggestions and it could act as an archive or library for town information. It's just the matter of taking it seriously and giving it an appropriate budget like they do with any other public structure or organization. But if it proves to be valuable component of public organization it would be budgeted and administered appropriately.