feat: evolve rate-filter to a more generic filter

internal/corecfg/merge.go

@@ -51,6 +51,23 @@ func popFirstProxyGroup(data map[string]interface{}) map[string]interface{} {
 // folding every merged subscription's default selector group together.
 const selectionGroupName = "Proxy Selection"
 
+// rewritePoppedGroupRef reflects, in a subscription's own proxy-group refs,
+// that its first group was just popped off (via popFirstProxyGroup) to be
+// folded into the shared selectionGroupName group by mergeProxySelection —
+// so an ssm rule matching this subscription's original default-selector
+// name (e.g. via match.name-pattern) resolves to the DisplayName that will
+// actually exist in the final config, not one that's about to disappear.
+// groupRefs must be in the same order popFirstProxyGroup pops from (i.e.
+// straight from automation.PrefixProxyNames), so index 0 is always the
+// popped group. No-op if groupRefs is empty.
+func rewritePoppedGroupRef(groupRefs []automation.ProxyRef) []automation.ProxyRef {
+	if len(groupRefs) == 0 {
+		return groupRefs
+	}
+	groupRefs[0].DisplayName = selectionGroupName
+	return groupRefs
+}
+
 // mergeProxySelection collapses each subscription's default selector group
 // (already popped off by popFirstProxyGroup) into a single combined group
 // named selectionGroupName, covering every subscription's proxies, and