[ greenart7c3/Amber ] feat: Add `lastUsed` field to application entity

This commit introduces a `lastUsed` timestamp to the `ApplicationEntity`.

This new field tracks the last time an application was used and is updated every time a new history event is recorded.

The changes include:

* Updating the Room database schema to version 14.

* Adding a database migration to include the new `lastUsed` column.

* Populating the `lastUsed` field on application creation and when adding history.

https://github.com/greenart7c3/Amber/commit/77500e7b496306e8a6ae3b76a1cea36c421d85f2