chore(pentest): genericize target URL placeholder

Replace the staging-specific hostname with a generic "your.staging.app"
so the placeholder doesn't imply a Comp AI internal target.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: tofikwest

apps/app/src/app/(app)/[orgId]/security/penetration-tests/_components/CreateRunPanel.tsx

@@ -107,7 +107,7 @@ export function CreateRunPanel({
                 id="pt-target-url"
                 value={targetUrl}
                 onChange={(e) => setTargetUrl(e.target.value)}
-                placeholder="app.staging.trycomp.ai"
+                placeholder="your.staging.app"
                 autoFocus
                 required
                 className="flex-1 bg-transparent font-mono text-xs outline-none"