This uses the code from my ChecklistEditor repo at https://github.com/gamernator8192/ChecklistEditor/ in a Spring Boot Framework... whatever you call something that uses the SBF. Because this is obviously what one does with checklists. The README from ChecklistEditor is below, for reference.
Simple checklists stored in plain text files.
Items are separated by lines. An incomplete item is prefaced with [ ], while a completed item is prefaced with [*].
[ ] incomplete
[*] complete
Notes about an item can optionally be added by separating them with a | character.
[ ] item without notes
[ ] item with notes | here are the notes
[ ] but this|does not work because there is no space
[ ] also | this | does | not | work | very | well
[ ] (it will just become "also | this")
Lists can be divided into headings. I have no idea how to verbally explain my heading denotation scheme.
[ ] uncategorized item
[ ] these are expected to come before any sort of heading
~~ heading 1 ~~
[ ] this item is under heading 1
[ ] this item is also under heading 1
~ subheading
[ ] those are things, but only one deep (for now?)
~~ heading 2 ~~
[ ] oh snap this item is under heading 2
[ ] bet nobody saw that coming
[ ] this item is still under heading 2
[ ] but empty lines within a heading are discouraged
[ ] i.e. i'm too lazy to make the application support them :p
[ ] meaning they'll get erased, not weirdly categorized
[ ] all this is still under heading 2, but if this list were loaded and then saved
[ ] the blank lines would get erased
[ ] but do put one blank line between top-level headers
~~ like this ~~
[ ] notice the blank line above the header title
[ ] yeah that's what you're supposed to do
[*] i promise all this makes sense in my head