refactor(db): replace sqlc with handwritten pgx repos

- Finish Paddle-to-Stripe billing migration; drop paddle/stripe libs
- Renumber migrations; add 00012 memberships+manage_token,
  00013 location_type_capacity
- Add tests: admin, auth, bookings customer service
- Remove graphify-out artifacts and stale env files

Authored By: TDvorak <[email protected]>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/backend/internal/notifications/service.go

@@ -126,7 +126,7 @@ func (s *Service) SendBookingConfirmation(ctx context.Context, data BookingEmail
 		data.BusinessEmail = s.cfg.EmailFrom
 	}
 	data.Type = EmailTypeConfirmation
-	msg := RenderEmailMessage(data)
+	msg := s.renderWithOverride(ctx, data)
 	_, err := s.emailProvider.Send(ctx, msg)
 	return err
 }
@@ -137,7 +137,7 @@ func (s *Service) SendBookingReschedule(ctx context.Context, data BookingEmailDa
 		data.BusinessEmail = s.cfg.EmailFrom
 	}
 	data.Type = EmailTypeReschedule
-	msg := RenderEmailMessage(data)
+	msg := s.renderWithOverride(ctx, data)
 	_, err := s.emailProvider.Send(ctx, msg)
 	return err
 }
@@ -148,11 +148,73 @@ func (s *Service) SendBookingCancellation(ctx context.Context, data BookingEmail
 		data.BusinessEmail = s.cfg.EmailFrom
 	}
 	data.Type = EmailTypeCancellation
-	msg := RenderEmailMessage(data)
+	msg := s.renderWithOverride(ctx, data)
 	_, err := s.emailProvider.Send(ctx, msg)
 	return err
 }
 
+// renderWithOverride renders the default message and, when the tenant has an
+// enabled custom template for this email type, swaps in the stored subject and
+// body with {{variable}} substitution.
+func (s *Service) renderWithOverride(ctx context.Context, data BookingEmailData) EmailMessage {
+	msg := RenderEmailMessage(data)
+	if s.repo == nil || data.TenantID == "" {
+		return msg
+	}
+	tpl, err := s.repo.GetEmailTemplate(ctx, data.TenantID, string(data.Type))
+	if err != nil || !tpl.IsEnabled {
+		return msg
+	}
+	vars := map[string]string{
+		"customerName":  data.CustomerName,
+		"customerEmail": data.CustomerEmail,
+		"service":       data.Service,
+		"location":      data.Location,
+		"reference":     data.Reference,
+		"startsAt":      formatLocalizedDateTime(data.StartsAt, data.Timezone, data.Locale),
+		"tenantName":    data.TenantName,
+		"manageUrl":     data.ManagementURL,
+	}
+	if tpl.Subject != "" {
+		msg.Subject = substituteTemplateVars(tpl.Subject, vars)
+	}
+	if tpl.BodyText != "" {
+		msg.Text = substituteTemplateVars(tpl.BodyText, vars)
+		if tpl.BodyHTML == "" {
+			msg.HTML = wrapTextAsHTML(msg.Text, data.BrandColor, data.TenantName, data.ManagementURL)
+		}
+	}
+	if tpl.BodyHTML != "" {
+		msg.HTML = substituteTemplateVars(tpl.BodyHTML, vars)
+	}
+	return msg
+}
+
+func substituteTemplateVars(body string, vars map[string]string) string {
+	for key, value := range vars {
+		body = strings.ReplaceAll(body, "{{"+key+"}}", value)
+	}
+	return body
+}
+
+func wrapTextAsHTML(text, brandColor, tenantName, manageURL string) string {
+	if brandColor == "" {
+		brandColor = "#c25e3a"
+	}
+	html := "<html><body style='font-family: Arial, sans-serif; line-height: 1.6; color: #333;'>"
+	html += "<div style='max-width: 600px; margin: 0 auto; padding: 20px;'>"
+	html += fmt.Sprintf("<h2 style='color: %s; margin-bottom: 20px;'>%s</h2>", brandColor, tenantName)
+	for _, p := range splitParagraphs(text) {
+		if len(p) > 0 {
+			html += fmt.Sprintf("<p style='margin-bottom: 10px;'>%s</p>", p)
+		}
+	}
+	if manageURL != "" {
+		html += fmt.Sprintf("<div style='margin-top: 30px;'><a href='%s' style='display: inline-block; background: %s; color: white; padding: 12px 24px; text-decoration: none; border-radius: 6px;'>Manage Booking</a></div>", manageURL, brandColor)
+	}
+	return html + "</div></body></html>"
+}
+
 // SendBusinessNotification sends a notification to the business about a new booking
 func (s *Service) SendBusinessNotification(ctx context.Context, businessEmail string, data BookingEmailData) error {
 	if businessEmail == "" {
@@ -311,22 +373,24 @@ func (s *Service) SendUsageWarning(ctx context.Context, tenantID string, locatio
 		return fmt.Errorf("failed to get tenant: %w", err)
 	}
 
-	// Use a placeholder admin email - in production, would get from tenant owner
-	adminEmail := "admin@" + tenant.Slug + ".bookra.eu"
+	ownerEmail, err := s.repo.GetTenantOwnerEmail(ctx, tenantID)
+	if err != nil || ownerEmail == "" {
+		return nil
+	}
 
 	emailData := UsageNotificationData{
 		Type:          EmailTypeUsageWarning,
 		TenantName:    tenant.Name,
 		TenantSlug:    tenant.Slug,
 		BusinessEmail: s.cfg.EmailFrom,
-		AdminEmail:    adminEmail,
+		AdminEmail:    ownerEmail,
 		Locale:        tenant.Locale,
 		PlanCode:      tenant.PlanCode,
 		LocationCount: locationCount,
 		LocationLimit: locationLimit,
 		UsagePercent:  usagePercent,
-		UpgradeURL:    "https://bookra.eu/pricing",
-		DashboardURL:  "https://bookra.eu/dashboard",
+		UpgradeURL:    strings.TrimRight(s.cfg.FrontendURL, "/") + "/dashboard/billing",
+		DashboardURL:  strings.TrimRight(s.cfg.FrontendURL, "/") + "/dashboard",
 	}
 
 	msg := RenderUsageNotificationEmail(emailData)
@@ -348,19 +412,21 @@ func (s *Service) SendTrialEndingEmail(ctx context.Context, tenantID string, day
 		return fmt.Errorf("failed to get tenant: %w", err)
 	}
 
-	// Use a placeholder admin email - in production, would get from tenant owner
-	adminEmail := "admin@" + tenant.Slug + ".bookra.eu"
+	ownerEmail, err := s.repo.GetTenantOwnerEmail(ctx, tenantID)
+	if err != nil || ownerEmail == "" {
+		return nil
+	}
 
 	emailData := UsageNotificationData{
 		Type:          EmailTypeTrialEnding,
 		TenantName:    tenant.Name,
 		TenantSlug:    tenant.Slug,
 		BusinessEmail: s.cfg.EmailFrom,
-		AdminEmail:    adminEmail,
+		AdminEmail:    ownerEmail,
 		Locale:        tenant.Locale,
 		PlanCode:      tenant.PlanCode,
-		UpgradeURL:    "https://bookra.eu/pricing",
-		DashboardURL:  "https://bookra.eu/dashboard",
+		UpgradeURL:    strings.TrimRight(s.cfg.FrontendURL, "/") + "/dashboard/billing",
+		DashboardURL:  strings.TrimRight(s.cfg.FrontendURL, "/") + "/dashboard",
 	}
 
 	msg := RenderUsageNotificationEmail(emailData)