Validation: Queens email branding — brand_color placeholder

Verdict: PASS

Checks

• [x] action.html: 10 instances of {{brand_color}}, 0 instances of #d42026
• [x] announcement.html: 13 instances of {{brand_color}}
• [x] notification.html: 9 instances of {{brand_color}}
• [x] load_email_template() defaults brand_color to #d42026 when not provided
• [x] Queens email with brand_color=#e91e8c renders pink, no red
• [x] Kings email without brand_color renders red (default)
• [x] Pod running, pipeline green (#359 all steps success)