* docs: Update the documentation structure in the todo list
* add full index
* titlesonly
* move documentation to reference
* docs: Nest BPMN elements under a new "Elements of BPMN" section
* not hidden
* docs: Mark first three TODO items as completed
* fix: Uncheck incorrect checkboxes in todo.md
* move
* move building diagrams to own section
* renames
* docs
* move to explanation
* explanation
* reorder
* move forms
* rm todo
* typo
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Co-authored-by: burnettk <burnettk@users.noreply.github.com>