bug: obs_seq_coverage does not recognize all QC metadata generated by obs converters

Describe the bug

1. Create or find an obs_seq file which has a platform QC metadata which is not found in the hard-coded list in subroutine find_our_copies (Quality Control, NCEP QC index, DART quality control) (see attached; remove the TXT, then tar -z -x -f).
2. Feed it to obs_seq_coverage.
3. Expect a file with a list of locations where repeated obs are taken.
4. Program fails (see attached).

Error Message

find_qc_indices metadata:source Quality Control copyindex not found

Which model(s) are you working with? WACCM-X, but that's not relevant

Version of DART

Which version of DART are you using? Manhattan, circa 2022-10 and older

Have you modified the DART code?

No
A short term fix is to add "COSMIC QC" to the series of "if" statements.
But a more general possibility is to define a namelist variable that contains a list of permissible QC metadata.
Then any user can provide new values without debugging or asking us, plus modifying the code and recompiling.
This is an issue for other programs too, but I have not identified all of them yet.

Build information

Please describe:

1. The machine you are running on (e.g. windows laptop, NCAR supercomputer Cheyenne). Any
2. The compiler you are using (e.g. gnu, intel). Any
   obs_seq_coverage_io.tgz.TXT

Start with the obs_seq_coverage entry point and inspect the find_our_copies and find_qc_indices subroutines, especially their handling of QC metadata. Reproduce the failure with the attached obs_seq_coverage_io archive and the reported COSMIC QC value. Done means obs_seq_coverage accepts QC metadata generated by obs converters and produces the repeated-observation location list without failing.