This function adds a new column text_unique
to each events table that
creates unique identifiers for each occurrence of the same event message
by appending a count number. This prevents events like "GOAL" from being
merged across all separate goals.
add_unique_event_identifiers(events_list)
Updated events list with text_unique
column added to each
data frame
A list of event data frames (one per block)
This function is called by the exposed wrapper load_asc()