Add automatic reporting for missing text entries

Every now and then a missing text entry shows up.
Sins the process for resolving this is semi-manual it would be great to have an automatic reporting system for those missing keys.
Maybe this should happen on the server, maybe it should happen on the client. Both have their benefits.

No files, tests, or entry points are named. Start by locating the frontend text-entry lookup and tracing how missing keys are handled; then determine whether reporting belongs on the client or server. Done means missing keys are automatically reported through a defined workflow.

Written by the indexing model from the issue text.