Convert high frequency sentry errors to metric

[data-sync-user]

There are a number of frequently occurring Sentry errors that we should just convert to simple metrics. These are highly specific and generally non-actionable.

• ApiError: Invalid router type for adm routers. (We have long since dropped ADM as a valid router type. We should include some comment indicating that this was previously valid in case we have to re-enable ADM routing.
• ApiError: User has invalid app ID smartphone-browser-lujo An unknown smartphone device regularly tries to register. It fails.

Since these errors are non-actionable, but still of passing interest, we should convert them to a metric that will eventually be part of the Autopush dashboard as “annoyances”.

┆Issue is synchronized with this Jira Task