Usability

- [x] need `hasAttribute -> bool`
- [x] need small example to parse a single float value
- [ ] the root thing isn't very pretty while parsing, should be able to iterate from the document
- [ ] a getter for converting .innerText to a string/int/bool and get that while ensuring uniqueness of the tag name

No files or tests are named. Start at the parser's document/root entry point and review the existing hasAttribute behavior and single-float parsing example; clarify the desired document iteration and typed innerText getter semantics, then add focused coverage showing uniqueness and the supported conversions.

Written by the indexing model from the issue text.