v0.88.0: app-email SMTP relay (in-process shim + per-app injection)

In-process go-smtp shim (Shape 1): apps → shim → hub → Resend, Resend key stays
hub-side. From-header allowlist (reject 5xx pre-hub), single-shot raw-MIME forward,
status→SMTP mapping. Global + per-app toggles gate compose-time env injection from
.felhom.yml smtp_mapping. Hungarian UI on settings + app config pages.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

controller/internal/web/handlers.go

@@ -398,6 +398,23 @@ func (s *Server) deployHandler(w http.ResponseWriter, r *http.Request, name stri
 			}
 			data["CurrentValues"] = optValues
 		}
+
+		// App-email per-app toggle — only for apps that declare an smtp_mapping. Shown with
+		// honest context whether or not the global toggle is on.
+		if supported, enabled := s.stackMgr.AppEmailStatus(name); supported {
+			data["AppEmailSupported"] = true
+			data["AppEmailAppOn"] = enabled
+			data["AppEmailGlobalOn"] = s.settings.AppEmailEnabled()
+			local := meta.SMTPMapping.FromLocal
+			if local == "" {
+				local = meta.Slug
+			}
+			domain := "felhom.eu"
+			if len(s.cfg.MailRelay.FromDomains) > 0 && s.cfg.MailRelay.FromDomains[0] != "" {
+				domain = s.cfg.MailRelay.FromDomains[0]
+			}
+			data["AppEmailFromAddress"] = local + "@" + domain
+		}
 	}
 
 	// Memory info for deploy page (only for non-deployed apps)
@@ -881,6 +898,13 @@ func (s *Server) settingsData() map[string]interface{} {
 
 	data["NotificationPrefs"] = s.settings.GetNotificationPrefs()
 
+	// App-email (SMTP relay) — global toggle. Only meaningful when a hub is configured (the relay
+	// path runs through the hub); the template hides the control otherwise.
+	appEmail := s.settings.GetAppEmail()
+	data["AppEmailEnabled"] = appEmail.Enabled
+	data["AppEmailFromName"] = appEmail.FromName
+	data["AppEmailAvailable"] = s.cfg.Hub.URL != "" && s.cfg.MailRelay.HardEnabled()
+
 	// Storage paths with display data
 	storagePaths := s.settings.GetStoragePaths()
 	connectedCount := 0
@@ -1101,6 +1125,40 @@ func (s *Server) settingsNotificationsHandler(w http.ResponseWriter, r *http.Req
 	s.executeTemplate(w, r, "settings", data)
 }
 
+// settingsAppEmailHandler saves the global app-email toggle and starts/stops the on-box
+// SMTP shim to match (no controller restart needed).
+func (s *Server) settingsAppEmailHandler(w http.ResponseWriter, r *http.Request) {
+	_ = r.ParseForm()
+	enabled := r.FormValue("app_email_enabled") == "on" || r.FormValue("app_email_enabled") == "true"
+	fromName := strings.TrimSpace(r.FormValue("app_email_from_name"))
+
+	data := s.settingsData()
+	if err := s.settings.SetAppEmail(enabled, fromName); err != nil {
+		s.logger.Printf("[ERROR] [web] Failed to save app-email toggle: %v", err)
+		data["AppEmailError"] = "Hiba az alkalmazás-email beállítás mentésekor"
+		s.executeTemplate(w, r, "settings", data)
+		return
+	}
+	// Reconcile the shim's running state with the new toggle.
+	if s.mailShim != nil {
+		if err := s.mailShim.Apply(enabled); err != nil {
+			s.logger.Printf("[ERROR] [web] app-email shim could not be %s: %v", map[bool]string{true: "started", false: "stopped"}[enabled], err)
+			data = s.settingsData()
+			data["AppEmailError"] = "A beállítás elmentve, de az email-szolgáltatás indítása nem sikerült."
+			s.executeTemplate(w, r, "settings", data)
+			return
+		}
+	}
+	s.logger.Printf("[INFO] [web] App-email globally %s (from_name=%q)", map[bool]string{true: "enabled", false: "disabled"}[enabled], fromName)
+	data = s.settingsData()
+	if enabled {
+		data["AppEmailSuccess"] = "Alkalmazás-email bekapcsolva. Kapcsold be az egyes alkalmazásoknál is, ahol email-küldést szeretnél."
+	} else {
+		data["AppEmailSuccess"] = "Alkalmazás-email kikapcsolva."
+	}
+	s.executeTemplate(w, r, "settings", data)
+}
+
 func (s *Server) settingsNotificationsTestHandler(w http.ResponseWriter, r *http.Request) {
 	data := s.settingsData()