Comments made before initially clicking/creating BlackBoard LTI link don't get counted

[shortland]

Create work
Create comments on work
Add to BlackBoard Assignment
Click on assignment as student
Create second comment

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Only that second comment gets counted since LTI didn't exist on the work before then.

[shortland]

Once anyone visits Marginalia work thru BB LTI for the first time, should check if they had existing comments...

data/LTI/... dir should be created regardless initially when creating the work