jsahpxharpnit: always submit jobs in "obs" mode
jsahpxharpnit: submit to jsa_proc rather than CADC

Also add --local-add-info option for adding observation info
to existing jobs.
jsahpxharpnit: use jsa_pub_asn_id for obsinfo

Use this ORAC-DR frame class method to generate the JSA "public"
association identifier, and use this in the obsinfo for HARP.
jsahpxharpnit: prepare jobs in "night" mode

We need to prepare the jobs in "night" mode in order to get
the expected association IDs, but then to force submission
as "obs" mode in order only to save the obs products.