test: add 4 decode regression tests for recently fixed packets

- entity_equipment 1.8 (nbt TAG_End fix)
- entity_equipment 26.2 (topBitSetTerminatedArray fix)
- entity_metadata 1.8 (entityMetadataLoop mergeCompareTo)
- spawn_entity_living 1.8 (entityMetadata mergeCompareTo)

These ensure packets that were previously broken stay working.

cmd/strom/print_replay/testdata/reg_55_2b76af8b937b1e8f_test.go

@@ -0,0 +1,18 @@
+package failed_packets_test
+
+import (
+	"bytes"
+	"testing"
+
+	generated "github.com/admin-else/strom/mc/proto_generated/v1_8"
+)
+
+// Decode regression: spawn_entity_living (1.8) - entityMetadata mergeCompareTo
+func TestRegressionPacket2B76AF8B937B1E8F(t *testing.T) {
+	p := &generated.PlayToClientPacketSpawnEntityLiving{}
+	b := bytes.NewReader([]byte{0x4c, 0x65, 0xff, 0xff, 0xed, 0x66, 0x0, 0x0, 0x7, 0xe0, 0x0, 0x0, 0x29, 0xe6, 0x91, 0x0, 0x91, 0x0, 0x0, 0xfd, 0x8d, 0x0, 0x0, 0x0, 0x0, 0x21, 0x1, 0x2c, 0x82, 0x0, 0x12, 0x4, 0x3, 0x0, 0x4, 0x0, 0x66, 0x41, 0x20, 0x0, 0x0, 0x47, 0x0, 0x0, 0x0, 0x0, 0x8, 0x0, 0x9, 0x0, 0xc, 0x0, 0xf, 0x0, 0x7f})
+	err := p.Decode(b)
+	if err != nil {
+		t.Fatalf("regression: decode failed: %v", err)
+	}
+}