Pass --no-auto-update to CLI across all SDKs

Prevents the CLI from auto-updating itself, ensuring the version bundled
with the SDK is the version that runs.

Author: SteveSandersonMS

dotnet/src/Client.cs

@@ -883,7 +883,7 @@ private async Task VerifyProtocolVersionAsync(Connection connection, Cancellatio
             args.AddRange(options.CliArgs);
         }
 
-        args.AddRange(["--headless", "--log-level", options.LogLevel]);
+        args.AddRange(["--headless", "--no-auto-update", "--log-level", options.LogLevel]);
 
         if (options.UseStdio)
         {

go/client.go

@@ -1313,7 +1313,7 @@ func (c *Client) verifyProtocolVersion(ctx context.Context) error {
 // This spawns the CLI server as a subprocess using the configured transport
 // mode (stdio or TCP).
 func (c *Client) startCLIServer(ctx context.Context) error {
-	args := []string{"--headless", "--log-level", c.options.LogLevel}
+	args := []string{"--headless", "--no-auto-update", "--log-level", c.options.LogLevel}
 
 	// Choose transport mode
 	if c.useStdio {

nodejs/src/client.ts

@@ -986,6 +986,7 @@ export class CopilotClient {
             const args = [
                 ...this.options.cliArgs,
                 "--headless",
+                "--no-auto-update",
                 "--log-level",
                 this.options.logLevel,
             ];

python/copilot/client.py

@@ -1116,7 +1116,7 @@ async def _start_cli_server(self) -> None:
         if not os.path.exists(cli_path):
             raise RuntimeError(f"Copilot CLI not found at {cli_path}")
 
-        args = ["--headless", "--log-level", self.options["log_level"]]
+        args = ["--headless", "--no-auto-update", "--log-level", self.options["log_level"]]
 
         # Add auth-related flags
         if self.options.get("github_token"):