Sync library with live findings: raw socket docs, wire reply parsing, pack-id BMS, empty-slot guard

tests/test_battery.py

@@ -59,3 +59,17 @@ class TestBmsSoc(unittest.TestCase):
                                      data={"id": 2})
         self.assertEqual(env.to_dict()["dataArea"], {"opt": 0, "id": 2})
         self.assertEqual(env.cmd_type, 1705)
+
+    def test_empty_pack_slot_skipped(self):
+        from franklinwh_agate_client.battery import _is_empty_pack
+        reply = {"dataArea": {"opt": 0, "result": 0, "id": 0, "batSoc": 0,
+                              "batSoh": 0, "batTotalVolt": 0}}
+        self.assertTrue(_is_empty_pack(
+            reply, {"value": 0.0, "source": "batSoc"}))
+
+    def test_genuine_zero_pack_kept(self):
+        from franklinwh_agate_client.battery import _is_empty_pack
+        reply = {"dataArea": {"opt": 0, "result": 0, "id": 1, "batSoc": 0,
+                              "batSoh": 96, "batTotalVolt": 512}}
+        self.assertFalse(_is_empty_pack(
+            reply, {"value": 0.0, "source": "batSoc"}))