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/examples/basic.py

@@ -0,0 +1,140 @@
+#!/usr/bin/env python3
+"""
+BaraDB Python Client — Basic Examples
+
+This script demonstrates common operations with the BaraDB Python client.
+Run it while a BaraDB server is listening on localhost:9472.
+"""
+
+import sys
+
+from baradb import Client, QueryBuilder, WireValue
+
+
+def example_connection():
+    print("=== Connection ===")
+    client = Client("localhost", 9472)
+    client.connect()
+    print(f"Connected: {client.is_connected()}")
+    print(f"Ping: {client.ping()}")
+    client.close()
+    print(f"Connected after close: {client.is_connected()}")
+    print()
+
+
+def example_context_manager():
+    print("=== Context Manager ===")
+    with Client("localhost", 9472) as client:
+        print(f"Inside context: {client.is_connected()}")
+        print(f"Ping: {client.ping()}")
+    print("Outside context: closed automatically")
+    print()
+
+
+def example_simple_query():
+    print("=== Simple Query ===")
+    with Client("localhost", 9472) as client:
+        result = client.query("SELECT 42 as answer, 'BaraDB' as db")
+        print(f"Columns: {result.columns}")
+        print(f"Rows: {result.rows}")
+        print(f"Row count: {result.row_count}")
+        for row in result:
+            print(f"  answer={row['answer']}, db={row['db']}")
+    print()
+
+
+def example_parameterized_query():
+    print("=== Parameterized Query ===")
+    with Client("localhost", 9472) as client:
+        result = client.query_params(
+            "SELECT $1 as num, $2 as txt, $3 as flag",
+            [
+                WireValue.int64(123),
+                WireValue.string("hello world"),
+                WireValue.bool_val(True),
+            ],
+        )
+        for row in result:
+            print(f"  num={row['num']}, txt={row['txt']}, flag={row['flag']}")
+    print()
+
+
+def example_query_builder():
+    print("=== Query Builder ===")
+    with Client("localhost", 9472) as client:
+        sql = (
+            QueryBuilder(client)
+            .select("id", "name")
+            .from_("users")
+            .where("active = true")
+            .order_by("name", "ASC")
+            .limit(5)
+            .build()
+        )
+        print(f"Generated SQL: {sql}")
+    print()
+
+
+def example_vector():
+    print("=== Vector Value ===")
+    with Client("localhost", 9472) as client:
+        result = client.query_params(
+            "SELECT $1 as embedding",
+            [WireValue.vector([0.1, 0.2, 0.3, 0.4])],
+        )
+        for row in result:
+            print(f"  embedding type: {type(row['embedding'])}")
+    print()
+
+
+def example_ddl_dml():
+    print("=== DDL & DML ===")
+    with Client("localhost", 9472) as client:
+        # Clean up
+        try:
+            client.execute("DROP TABLE IF EXISTS demo_products")
+        except Exception as exc:
+            print(f"Cleanup warning: {exc}")
+
+        client.execute(
+            "CREATE TABLE demo_products (id INT PRIMARY KEY, name STRING, price FLOAT)"
+        )
+        affected = client.execute(
+            "INSERT INTO demo_products (id, name, price) VALUES (1, 'Widget', 9.99)"
+        )
+        print(f"Insert affected rows: {affected}")
+
+        result = client.query("SELECT * FROM demo_products")
+        print(f"Select returned {result.row_count} row(s)")
+        for row in result:
+            print(f"  {row}")
+
+        client.execute("DROP TABLE demo_products")
+        print("Table dropped")
+    print()
+
+
+def main():
+    print("BaraDB Python Client Examples")
+    print("Make sure BaraDB is running on localhost:9472")
+    print()
+
+    examples = [
+        example_connection,
+        example_context_manager,
+        example_simple_query,
+        example_parameterized_query,
+        example_query_builder,
+        example_vector,
+        example_ddl_dml,
+    ]
+
+    for fn in examples:
+        try:
+            fn()
+        except Exception as exc:
+            print(f"ERROR in {fn.__name__}: {exc}", file=sys.stderr)
+
+
+if __name__ == "__main__":
+    main()