feat(clients): professional clients with tests, CI/CD, and examples

- Python: pyproject.toml, pytest suite (unit + integration), README, examples
- JavaScript: package.json, TypeScript definitions, node:test suite, README, examples
- Nim: integration tests, examples, README, improved nimble tasks
- Rust: fixed nodelay/localhost IPv6 bug, integration tests, examples, README
- Added GitHub Actions CI for all 4 clients against Docker server
- Added docker-compose.test.yml for local integration testing
- Added .gitignore for each client

clients/python/tests/test_wire_protocol.py

@@ -0,0 +1,142 @@
+"""
+Unit tests for BaraDB Python client wire protocol.
+No running server required.
+"""
+
+import struct
+import pytest
+from baradb import WireValue, FieldKind, MsgKind, ResultFormat
+
+
+class TestWireValue:
+    """Tests for WireValue serialization / deserialization."""
+
+    def test_null(self):
+        wv = WireValue.null()
+        assert wv.kind == FieldKind.NULL
+        data = wv.serialize()
+        assert data == b"\x00"
+
+    def test_bool_true(self):
+        wv = WireValue.bool_val(True)
+        assert wv.serialize() == b"\x01\x01"
+
+    def test_bool_false(self):
+        wv = WireValue.bool_val(False)
+        assert wv.serialize() == b"\x01\x00"
+
+    def test_int8(self):
+        wv = WireValue.int8(-42)
+        data = wv.serialize()
+        assert data[0] == FieldKind.INT8
+        assert struct.unpack(">b", data[1:])[0] == -42
+
+    def test_int16(self):
+        wv = WireValue.int16(-1000)
+        data = wv.serialize()
+        assert data[0] == FieldKind.INT16
+        assert struct.unpack(">h", data[1:])[0] == -1000
+
+    def test_int32(self):
+        wv = WireValue.int32(123456)
+        data = wv.serialize()
+        assert data[0] == FieldKind.INT32
+        assert struct.unpack(">i", data[1:])[0] == 123456
+
+    def test_int64(self):
+        wv = WireValue.int64(9999999999)
+        data = wv.serialize()
+        assert data[0] == FieldKind.INT64
+        assert struct.unpack(">q", data[1:])[0] == 9999999999
+
+    def test_float32(self):
+        wv = WireValue.float32(3.14)
+        data = wv.serialize()
+        assert data[0] == FieldKind.FLOAT32
+        assert abs(struct.unpack(">f", data[1:])[0] - 3.14) < 0.01
+
+    def test_float64(self):
+        wv = WireValue.float64(2.718281828)
+        data = wv.serialize()
+        assert data[0] == FieldKind.FLOAT64
+        assert abs(struct.unpack(">d", data[1:])[0] - 2.718281828) < 1e-9
+
+    def test_string(self):
+        wv = WireValue.string("hello")
+        data = wv.serialize()
+        assert data[0] == FieldKind.STRING
+        length = struct.unpack(">I", data[1:5])[0]
+        assert length == 5
+        assert data[5:] == b"hello"
+
+    def test_bytes(self):
+        wv = WireValue.bytes_val(b"\xde\xad\xbe\xef")
+        data = wv.serialize()
+        assert data[0] == FieldKind.BYTES
+        length = struct.unpack(">I", data[1:5])[0]
+        assert length == 4
+        assert data[5:] == b"\xde\xad\xbe\xef"
+
+    def test_vector(self):
+        wv = WireValue.vector([1.0, 2.0, 3.0])
+        data = wv.serialize()
+        assert data[0] == FieldKind.VECTOR
+        dim = struct.unpack(">I", data[1:5])[0]
+        assert dim == 3
+        floats = [struct.unpack(">f", data[5 + i * 4 : 9 + i * 4])[0] for i in range(3)]
+        assert floats == [1.0, 2.0, 3.0]
+
+    def test_json(self):
+        wv = WireValue.json_val('{"key": "value"}')
+        data = wv.serialize()
+        assert data[0] == FieldKind.JSON
+        length = struct.unpack(">I", data[1:5])[0]
+        assert length == 16
+
+    def test_array(self):
+        inner = [WireValue.string("a"), WireValue.string("b")]
+        wv = WireValue.array_val(inner)
+        data = wv.serialize()
+        assert data[0] == FieldKind.ARRAY
+        count = struct.unpack(">I", data[1:5])[0]
+        assert count == 2
+
+    def test_object(self):
+        inner = {"name": WireValue.string("Bara"), "age": WireValue.int32(42)}
+        wv = WireValue.object_val(inner)
+        data = wv.serialize()
+        assert data[0] == FieldKind.OBJECT
+        count = struct.unpack(">I", data[1:5])[0]
+        assert count == 2
+
+
+class TestMessageKinds:
+    """Sanity checks for protocol constants."""
+
+    def test_client_kinds(self):
+        assert MsgKind.CLIENT_HANDSHAKE == 0x01
+        assert MsgKind.QUERY == 0x02
+        assert MsgKind.QUERY_PARAMS == 0x03
+        assert MsgKind.EXECUTE == 0x04
+        assert MsgKind.BATCH == 0x05
+        assert MsgKind.TRANSACTION == 0x06
+        assert MsgKind.CLOSE == 0x07
+        assert MsgKind.PING == 0x08
+        assert MsgKind.AUTH == 0x09
+
+    def test_server_kinds(self):
+        assert MsgKind.SERVER_HANDSHAKE == 0x80
+        assert MsgKind.READY == 0x81
+        assert MsgKind.DATA == 0x82
+        assert MsgKind.COMPLETE == 0x83
+        assert MsgKind.ERROR == 0x84
+        assert MsgKind.AUTH_CHALLENGE == 0x85
+        assert MsgKind.AUTH_OK == 0x86
+        assert MsgKind.SCHEMA_CHANGE == 0x87
+        assert MsgKind.PONG == 0x88
+        assert MsgKind.TRANSACTION_STATE == 0x89
+
+    def test_result_formats(self):
+        assert ResultFormat.BINARY == 0x00
+        assert ResultFormat.JSON == 0x01
+        assert ResultFormat.TEXT == 0x02