Merge text multi-section into vihaco-parser

[robpatterson13]

In #31 we have a separate chumsky parser to parse the vihaco multi-section format for text:

• we should rename this to sst to reflect the way it is currently structured and rename the binary format to be the "bytecode"
• merge the current text chumsky parser into vihaco-parser as a combination of the chumsky parser, that way everything lives in one place. We currently use vihaco_parser::Parse::parser().parse on the multi-section parsing (decided by the composite implementation) so it should live there anyways

[kaihsin]

In addition, evaluate chumsky for hierarchical parser for multi-section