feat: public explorer

[mfreeman451]

When threadr responds to questions on IRC or Discord, it should include a link to the new public explorer we'll create here.

The public explorer should be basically read only and just lets the user that clicked that link see the conversations that were referred to.

05:19 <@leku> threadr: what do sig and eefer talk about?
05:19 < threadr> leku: According to the context, specifically message [G4], sig and eefer talk about "crazy vidya if real" as indicated in message [G5].
05:19 < threadr> leku: Based on the provided context, sig and eefer talk about "crazy vidya" (likely meaning crazy video games or videos) as indicated in message [G5]: "##!chases eefer:
                 crazy vidya if real". No other information about sig and eefer's conversations is available in the given context.

If there were 20 messages between these two users, we probably wouldn't want to get the detailed summary in the chat window, we should keep the response fairly short and include a link to the full conversations.