Add MAILGUN_URL for EU region support

Mailgun EU accounts require api.eu.mailgun.net endpoint.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.env.example

@@ -14,6 +14,7 @@ NEXT_PUBLIC_POCKETBASE_URL=http://localhost:8090
 # Email (Mailgun)
 MAILGUN_API_KEY=key-xxxxxxxxxxxx
 MAILGUN_DOMAIN=yourdomain.com
+MAILGUN_URL=https://api.eu.mailgun.net  # Use https://api.mailgun.net for US region
 EMAIL_FROM=phaseflow@yourdomain.com
 
 # Encryption (for Garmin tokens)

src/lib/email.ts

@@ -17,6 +17,7 @@ function getMailgunClient(): IMailgunClient {
     mg = mailgun.client({
       username: "api",
       key: process.env.MAILGUN_API_KEY || "",
+      url: process.env.MAILGUN_URL || "https://api.mailgun.net",
     });
   }
   return mg;