feat: warn when defender config is omitted at construction time

SDK defaults will override project-level defender settings when no
explicit defender config is passed. A console.warn nudges users to
either pass an explicit config or opt into useProjectSettings: true.

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

Author: hiskudin

src/toolsets.ts

@@ -346,6 +346,14 @@ export class StackOneToolSet {
 			}
 		}
 		this.defenderConfig = defenderInput === undefined ? DEFAULT_DEFENDER_CONFIG : defenderInput;
+		if (defenderInput === undefined) {
+			console.warn(
+				'[StackOneToolSet] No defender config provided. SDK defaults are active and will override any ' +
+					'project-level defender settings. To use your project settings, pass ' +
+					'`defender: { useProjectSettings: true }`. To suppress this warning, pass an explicit ' +
+					'`defender` config.',
+			);
+		}
 
 		// Set Authentication headers if provided
 		if (this.authentication) {