Set default baud rate to 115200 (confirmed working with device)

Tested on COM1 - device responds correctly at 115200 baud with CR+LF
termination. Verified identify and measure commands work.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

prodigit3366g/cli.py

@@ -269,8 +269,8 @@ examples:
         help="Serial port (default: COM1)",
     )
     parser.add_argument(
-        "-b", "--baudrate", type=int, default=9600,
-        help="Baud rate (default: 9600)",
+        "-b", "--baudrate", type=int, default=115200,
+        help="Baud rate (default: 115200)",
     )
     parser.add_argument(
         "--timeout", type=float, default=2.0,

prodigit3366g/driver.py

@@ -43,7 +43,7 @@ class Prodigit3366G:
 
     Args:
         port: Serial port name, e.g. "COM1" or "/dev/ttyUSB0".
-        baudrate: Baud rate (must match front panel setting). Default 9600.
+        baudrate: Baud rate (must match front panel setting). Default 115200.
         timeout: Read timeout in seconds.
     """
 
@@ -61,7 +61,7 @@ class Prodigit3366G:
     def __init__(
         self,
         port: str = "COM1",
-        baudrate: int = 9600,
+        baudrate: int = 115200,
         timeout: float = 2.0,
     ) -> None:
         self._port_name = port