Improve TEXT fields sent from alertsActor to STS

After using the alertsActor and STS for a while, we have learnt of things to improve, especially about the content of the per-datum STS TEXT fields. When the data value is good we send "OK", when a problem we want to send something descriptive and helpful; for engineers, etc.

When the TEXT is not "OK", STS arranges to send the value and the text via email or SMS. These messages are proving to be confusing, most because important information is getting lost/truncated behind static text.

Some known issues:

• STS retains up to 200 chars from the input, and saves 40 in the database. These are hardcoded numbers, and we need to make sure that the text from alertActors is formatted to not waste the leading characters.
• there are also SMS limits, with the same need to use leading characters well.
• The "NO DATA" message from the alertsActor (describing loss-of-data from the actor) is not sufficiently distinct from the equivalent message from STS (describing loss-of-data from PFS).
• The "NO DATA" alertsActor message uses seconds-from-LOD, which changes with each message. This should be an absolute timestamp. This may not be essential for STS, but would be enormously helpful for other consumers.

Can Yoshida, Hiroshigearnaud.lefurcloomis, at least, meet and decide what to do?