Add ssl_verify config option to fix certificate errors

Raw OpenSSL sockets don't find the system CA bundle the same way Net::HTTP
does. ssl_verify (default: true) is now a config setting that applies to
both HTTP REST calls and WebSocket connections. Set via `portainer-cli configure`.

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

lib/portainer_cli/commands/configure.rb

@@ -32,6 +32,11 @@ module PortainerCli
           @config.api_key = prompt_secret("API key", @config.api_key)
         end
 
+        puts
+        current_verify = @config.ssl_verify.nil? ? true : @config.ssl_verify
+        verify_choice  = prompt("Verify SSL certificates? [y/n]", current_verify ? "y" : "n")
+        @config.ssl_verify = (verify_choice.downcase != "n")
+
         @config.save
         puts
         puts green("Configuration saved to #{Config::CONFIG_FILE}")