Function claims_of 

pub fn claims_of(
    app_id: &str,
    mutation: &DocumentMutation,
) -> Result<Vec<ChangeClaim>, ClaimError>

The claims of the changes mutation carries, a change this process made to a record of app_id, each naming as units what its action may write (with_footprints): what the op that carries it is signed with.

A change names what it is in its message. One store wrote a record’s first change with none: its schema stamp, a root change with no deps that only sets the old schema version key (tilo:schema_version). That change is the record’s creation by what it is, so it is claimed as one (collab_types::FrameworkChange::Genesis), as a store now names it when it writes it: a record whose first change is such a stamp is handed to a sealed workspace whole, with no change rewritten and no id changed.