Schema, Transform, Documentation for OV: `<said>` elements and quotation marks for OV

@Samwebb64 seeks clarification on `<said>` and `<q>` not ever taking literal quotation marks inside:

* Update Schema to make sure that curly quotes trigger our schema rule about quotation marks
* Make sure we have a way to signal (if needed) an unquoted spoken passage. 
* Otherwise our default is always to render `<q>` and `<said>` as pairs of matched quotes when we output files to HTML. 