Expand VENDOR_PROJECT_KEYS to include all vendor projects: AA_ADTRAN,
AA_ADVA, AA_CASA, AA_CISCO, AACOMMSCOP, AA_COMMSCOP, AA_HARMONI,
AA_JUNIPER, AA_VECIMA, AA_VIAVI. Both AACOMMSCOP and AA_COMMSCOP
variants are included for safety.
Update property tests to exercise the full vendor key list instead of
only AA_VECIMA. Update full-reference-manual.md with vendor-specific
issue type dropdown documentation.
