Add CLI run options, update README

cmd_chat/__init__.py

@@ -1,4 +1,5 @@
 import asyncio 
+import argparse
 
 from cmd_chat.server.server import app
 from cmd_chat.client.client import Client
@@ -28,23 +29,36 @@ async def run_client(
 
 
 async def run() -> None:
-    action: int = int(
-        input("Choose action:\n1. Run server\n2. Run client\nAction: ")
+    parser = argparse.ArgumentParser(
+        description='Command-line chat application'
     )
-    if action == 1:
-        await run_server(
-            input("IP: "),
-            int(input("PORT: "))
-        )
-    if action == 2:
-        await run_client(
-            input("USERNAME: "),
-            input("IP: "),
-            int(input("PORT: "))
-        )
+    parser.add_argument(
+        'command', 
+        choices=['serve', 'connect'], 
+        help='Command to execute'
+    )
+    parser.add_argument(
+        'ip_address', 
+        help='IP address to serve or connect'
+    )
+    parser.add_argument(
+        'port', 
+        help='PORT of server'
+    )
+    parser.add_argument(
+        'username', 
+        nargs='?', 
+        default='', 
+        help='Username for connection (required for connect command)'
+    )
+    args = parser.parse_args()
+    if args.command == 'serve':
+        await run_server(args.ip_address, int(args.port))
+    elif args.command == 'connect':
+        if not args.username:
+            parser.error("Username is required for 'connect' command")
+        await run_client(args.username, args.ip_address, int(args.port))
 
 
 if __name__ == '__main__':
-    asyncio.run(
-        run()
-    )
+    asyncio.run(run())