Truncate long messages that get auto submitted

[Jacob-Griffin]

We have a character limit that works all well and good by preventing the sender from clicking send. Problem: If an excessive message is in the bubble when time runs out, it can get sent anyway. The naive solution is to prevent the message from getting that long, but we don't really want to be in the business of triaging pasted text that's in the middle of a message. The next easy solution, and the one I plan to go with is to truncate the message if that happens. While the character count turning red should be an indicator that their message will get truncated if it auto submits, there should be an inline indicator of which characters are subject to truncation just to be extra clear. So:

• [x] Make sure messages get truncated to 280 characters before they're sent
• [x] Investigate the possibility of highlighting or recoloring just the text that exceeds the character limit

[Jacob-Griffin]

Messages are truncated to max message length right before sending. There is no way to highlight the text that goes over the limit, so we'll just rely on the ticking number and people can triage their text how they want