Register insights endpoint for topic recommendation

[camillecroci]

Adding metrics services for topic recommendation endpoint:
https://api.ft.com/snr/v1/insights/recommended-articles/{{USER_ID}}

Got a code scanning failure from CodeQL about escaping the . in api.ft.com:

Incomplete regular expression for hostnames
This regular expression has an unescaped '.' before 'ft.com', so it might match more hosts than expected.

so I added that to all the insights endpoints. Hopefully it should not cause any issue, or if it does, it means one of our services was not correctly registered and we can add it.