cmd/geth, consensus/ethash: add support for --miner.notify.full flag (#22558)

The PR implements the --miner.notify.full flag that enables full pending block
notifications. When this flag is used, the block notifications sent to mining
endpoints contain the complete block header JSON instead of a work package
array.

Co-authored-by: AlexSSD7 <alexandersadovskyi7@protonmail.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>

consensus/ethash/ethash_test.go

@@ -62,7 +62,14 @@ func TestCacheFileEvict(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer os.RemoveAll(tmpdir)
-	e := New(Config{CachesInMem: 3, CachesOnDisk: 10, CacheDir: tmpdir, PowMode: ModeTest}, nil, false)
+
+	config := Config{
+		CachesInMem:  3,
+		CachesOnDisk: 10,
+		CacheDir:     tmpdir,
+		PowMode:      ModeTest,
+	}
+	e := New(config, nil, false)
 	defer e.Close()
 
 	workers := 8