Add Messaging support to ping.pub / or other block explorer

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As a user of ping.pub I'd expect to find a way to post messages by user address from the block explorer or by following a link to dither I can post messages.

Here's similar feature from Etherscan

Above notice the icon 'Message user with blockscan chat'

Below we also see chat in the menu

I think ping-pub was mentioned as a good target
https://ping.pub/atomone

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One more screenshot - the actual messaging dialog.