Propagate new fallback model to all remaining script references

All FALLBACK_${MY_ID}_COVERS_${REMOTE_ID}_TIER* references updated to
FALLBACK_${REMOTE_ID}_TIER* across fallback_test.sh, partnership_manager.sh,
docker_update.sh, mesh_monitor.sh, and monitor.php. mesh_monitor.sh drops
the inner covering-host loop — tier data now lives in the covered host's own
conf so no cross-host scan is needed. monitor.php reads from the covered
host's conf file rather than the local host's.

Partnership/partnership_manager.sh

@@ -512,7 +512,7 @@ gather_partner_fallback_containers() {
     eval "${out_var}=()"
     local tier var
     for tier in TIER1 TIER2 TIER3 TIER4; do
-        var="FALLBACK_${MY_ID}_COVERS_${REMOTE_ID}_${tier}"
+        var="FALLBACK_${REMOTE_ID}_${tier}"
         # Check if var is set and is an array
         if declare -p "$var" >/dev/null 2>&1; then
             local -a _tmp_arr