[feature] Credentials Reporting

[KCarretto]

Describe the solution you'd like
Let's add a reportCredentials gRPC endpoint so that we can easily query captured credentials.

[hulto]

Well definitely run into repeats esp when doing reading CCDC password logs from Scoring engine.

Probably do an upsert to keep only one ent per user/pass pair.
Nervous to make the key just user cuz ppl typo often.