7302 add notes to outgoing and incoming messages

[HelenWDTK]

Relevant issue(s)

Based on #7302

What does this do?

Adds basic notes to incoming and outgoing messages

Why was this needed?

Allows display of things like upload links at the right spot in the thread

Implementation notes

Screenshots

Notes to reviewer

Needs more work to work with tags, but this'd be an improvement. Might want to change where we display these depending.

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