Add support for incremental loading

[Ameer2896]

From preliminary testing, I can see that loading nodes/edges into AGE through the csv loading technique replaces the previously existing nodes/edges. The label sequence seems to be reset, and new data is inserted from ID 1.
Due to this, it is not possible to do incremental loading, or periodic loading from other data sources using this tool.

It would be useful if the sequence number of the label is kept and incremented upon. This would also need handling of conflicts with already existing nodes/edges.

Is this something that is currently in scope for this tool?

[surendar-maharajah]

@rioriost is there any known way to load more csv files to AGE without deleting the existing data in AGE using agefreighter ?

[surendar-maharajah]

https://github.com/rioriost/agefreighter/blob/main/src/agefreighter/csvexporter.py#L547
can we remove/get the createGraph flag as input to allow updates from csv files

right now If i add a new csv file , it is clearing every thing from the table