Implement translation of raw string from notification into SQLite database entities.

Summary: This diff uses functions implemented in ptwo previous diffs to convert raw string into SQlite database entities

Test Plan: No testing plan. Future diffs will provide a code that uses those functions on iOS and Android respectively

Reviewers: palys-swm, karol-bisztyga

Reviewed By: palys-swm, karol-bisztyga

Subscribers: ashoat, Adrian, atul, yayabosh

Differential Revision: https://phab.comm.dev/D3984