core, eth, les, tests, trie: abstract node scheme (#25532)

This PR introduces a node scheme abstraction. The interface is only implemented by `hashScheme` at the moment, but will be extended by `pathScheme` very soon.

Apart from that, a few changes are also included which is worth mentioning:

-  port the changes in the stacktrie, tracking the path prefix of nodes during commit
-  use ethdb.Database for constructing trie.Database. This is not necessary right now, but it is required for path-based used to open reverse diff freezer

trie/database_test.go

@@ -20,13 +20,13 @@ import (
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/ethdb/memorydb"
+	"github.com/ethereum/go-ethereum/core/rawdb"
 )
 
 // Tests that the trie database returns a missing trie node error if attempting
 // to retrieve the meta root.
 func TestDatabaseMetarootFetch(t *testing.T) {
-	db := NewDatabase(memorydb.New())
+	db := NewDatabase(rawdb.NewMemoryDatabase())
 	if _, err := db.Node(common.Hash{}); err == nil {
 		t.Fatalf("metaroot retrieval succeeded")
 	}