Support EC+REP policies

[cthulhu-rider]

Is your feature request related to a problem? Please describe.

with #3570, EC policies became available, but mutually exclusive w/ REP ones. It can make sense to support container policies having both EC and REP encoding/placement rules

Describe the solution you'd like

Now

drop IR condition

mostly, code is already ok to work w/ both lists. But not everywhere. Two definite places i know are

neofs-node/pkg/services/object/put/distributed.go

Lines 174 to 198 in 1869725

	repRules := t.containerNodes.PrimaryCounts()
	if len(repRules) > 0 {
	typ := obj.Type()
	broadcast := typ == objectSDK.TypeTombstone || typ == objectSDK.TypeLink || (!t.localOnly && typ == objectSDK.TypeLock) || len(obj.Children()) > 0
	return t.distributeObject(obj, objMeta, encObj, func(obj objectSDK.Object, objMeta object.ContentMeta, encObj encodedObject) error {
	return t.placementIterator.iterateNodesForObject(obj.GetID(), repRules, objNodeLists, broadcast, func(node nodeDesc) error {
	return t.sendObject(obj, objMeta, encObj, node)
	})
	})
	}
	if ecRules := t.containerNodes.ECRules(); len(ecRules) > 0 {
	if t.ecPart.RuleIndex >= 0 { // already encoded EC part
	total := int(ecRules[t.ecPart.RuleIndex].DataPartNum + ecRules[t.ecPart.RuleIndex].ParityPartNum)
	nodes := objNodeLists[len(repRules)+t.ecPart.RuleIndex]
	return t.saveECPart(obj, objMeta, encObj, t.ecPart.Index, total, nodes)
	}
	if t.sessionSigner != nil {
	if err := t.ecAndSaveObject(t.sessionSigner, obj, ecRules, objNodeLists[len(repRules):]); err != nil {
	return err
	}
	}
	}

neofs-node/pkg/services/policer/check.go

Lines 121 to 125 in 1869725

	if ecp.RuleIndex >= 0 {
	if len(ecRules) > 0 {
	p.processECPart(ctx, addr, ecp, ecRules, nn[len(repRules):])
	return
	}

for analysis, look for https://pkg.go.dev/github.com/nspcc-dev/neofs-sdk-go/netmap#NetMap.ContainerNodes calls

Then

explore possible optimizations for rules' processing. For example, handling GET is likely more efficient via REP rules initially

Additional context

#526