This PR is [resolving the dispatch part of Coder
Inbocx](https://github.com/coder/internal/issues/403).
Since the DB layer has been merged - we now want to insert notifications
into Coder Inbox in parallel of the other delivery target.
To do so, we push two messages instead of one using the `Enqueue`
method.
This PR aims to close#14253
We keep the default behavior using the Coder logo if there's no logo
set.
Otherwise we want to use the logo based on the URL set in appearance.
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Co-authored-by: defelmnq <yvincent@coder.com>