Promo: order page + red banner + contact form; fix admin login rehash

- /order page: single tag $5.50 / 10-pack $22.00 (GST-incl), qty via
  Stripe Payment Links (single 1-25, pack 1-2), thanks state
- Red 'Protect & recover your valuables — ORDER NOW' banner in base layout
  (every page incl. found-dog tag page) + footer promo links
- Contact page: form -> Gmail SMTP (env SMTP_*), hello@where-woof.com
- Fix admin login 500: User.getAuthPasswordName() = password_hash so
  Laravel 13 rehash-on-login writes the correct column (was trying
  UPDATE users SET password = ...)

frontend/main.go

@@ -70,6 +70,8 @@ func main() {
 	mux.HandleFunc("GET /about", app.About)
 	mux.HandleFunc("GET /what-is-this", app.WhatIsThis)
 	mux.HandleFunc("GET /contact", app.Contact)
+	mux.HandleFunc("POST /contact", app.ContactSubmit)
+	mux.HandleFunc("GET /order", app.Order)
 	mux.HandleFunc("/{path...}", app.LegacyNotFound)
 	mux.HandleFunc("GET /t/{tag_code}", app.PublicTag)
 	mux.HandleFunc("GET /s/{code}", app.ServeShort)