feat(mail): sender display name (SMTP_FROM_NAME, default MindSift)

A bare SMTP_FROM address gets the display name in the From header; a name
already in SMTP_FROM wins, the envelope keeps the bare address. Also a
field in the admin mail settings.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/api/mail.go

@@ -20,8 +20,9 @@ import (
 // smtpSettings is the effective mail server configuration (admin settings, else environment).
 type smtpSettings struct {
 	Host, Port, User, Pass, From string
-	TLS                          bool // 465: implicit TLS, otherwise STARTTLS (required when set)
-	SkipVerify                   bool // accept self-signed / mismatching certificates
+	FromName                     string // display name when From is a bare address
+	TLS                          bool   // 465: implicit TLS, otherwise STARTTLS (required when set)
+	SkipVerify                   bool   // accept self-signed / mismatching certificates
 
 	authMech string // "" = automatic; "LOGIN" forces AUTH LOGIN (fallback after a refused PLAIN)
 }
@@ -46,13 +47,15 @@ func (s *Server) smtpSettings() (smtpSettings, error) {
 		cfg = smtpSettings{
 			Host: strings.TrimSpace(sys.SMTPHost), Port: strings.TrimSpace(sys.SMTPPort),
 			User: strings.TrimSpace(sys.SMTPUser), Pass: sys.SMTPPass, From: strings.TrimSpace(sys.SMTPFrom),
-			TLS: sys.SMTPTLS, SkipVerify: sys.SMTPSkipVerify,
+			FromName: strings.TrimSpace(sys.SMTPFromName),
+			TLS:      sys.SMTPTLS, SkipVerify: sys.SMTPSkipVerify,
 		}
 	} else if strings.TrimSpace(s.cfg.SMTPHost) != "" {
 		cfg = smtpSettings{
 			Host: strings.TrimSpace(s.cfg.SMTPHost), Port: strings.TrimSpace(s.cfg.SMTPPort),
 			User: strings.TrimSpace(s.cfg.SMTPUser), Pass: s.cfg.SMTPPass, From: strings.TrimSpace(s.cfg.SMTPFrom),
-			TLS: s.cfg.SMTPTLS, SkipVerify: s.cfg.SMTPSkipVerify,
+			FromName: strings.TrimSpace(s.cfg.SMTPFromName),
+			TLS:      s.cfg.SMTPTLS, SkipVerify: s.cfg.SMTPSkipVerify,
 		}
 	}
 	if cfg.Host == "" {
@@ -61,6 +64,9 @@ func (s *Server) smtpSettings() (smtpSettings, error) {
 	if cfg.Port == "" {
 		cfg.Port = "587"
 	}
+	if cfg.FromName == "" {
+		cfg.FromName = "MindSift"
+	}
 	if cfg.From == "" {
 		if strings.Contains(cfg.User, "@") {
 			cfg.From = cfg.User
@@ -96,6 +102,19 @@ func splitAddress(raw string) (envelope, header string, err error) {
 	return addr.Address, addr.String(), nil
 }
 
+// senderAddress is splitAddress for the sender: a bare address gets the display name, so mail clients
+// show "MindSift" instead of only the address. A name already in SMTP_FROM wins.
+func senderAddress(raw, name string) (envelope, header string, err error) {
+	addr, err := mail.ParseAddress(strings.TrimSpace(raw))
+	if err != nil {
+		return "", "", fmt.Errorf("ungültige E-Mail-Adresse %q", raw)
+	}
+	if addr.Name == "" {
+		addr.Name = strings.TrimSpace(name)
+	}
+	return addr.Address, addr.String(), nil
+}
+
 // buildMessage creates an RFC 5322 message: Date and Message-ID headers, RFC 2047 encoded subject
 // (umlauts, emoji) and a quoted-printable UTF-8 body with CRLF line endings.
 func buildMessage(from, to, subject, body string, now time.Time) []byte {
@@ -202,7 +221,7 @@ func sendMail(cfg smtpSettings, to, subject, body string) error {
 // sendMailOnce runs the SMTP dialogue step by step instead of smtp.SendMail, so it can introduce itself
 // properly, honour SkipVerify and report the exact step a server refuses.
 func sendMailOnce(cfg smtpSettings, to, subject, body string) error {
-	fromAddr, fromHeader, err := splitAddress(cfg.From)
+	fromAddr, fromHeader, err := senderAddress(cfg.From, cfg.FromName)
 	if err != nil {
 		return &smtpStepError{"Absender", err}
 	}

internal/api/mail_test.go

@@ -270,3 +270,17 @@ func TestAuthLoginOnlyAndBothFailing(t *testing.T) {
 		t.Fatalf("expected both mechanisms and the server hint in the error, got %v", err)
 	}
 }
+
+func TestSenderAddressGetsDisplayName(t *testing.T) {
+	cases := []struct{ raw, name, envelope, header string }{
+		{"alerts@example.com", "MindSift", "alerts@example.com", `"MindSift" <alerts@example.com>`},
+		{`"Mein Dienst" <alerts@example.com>`, "MindSift", "alerts@example.com", `"Mein Dienst" <alerts@example.com>`},
+		{"alerts@example.com", "Büro Müller", "alerts@example.com", "=?utf-8?q?B=C3=BCro_M=C3=BCller?= <alerts@example.com>"},
+	}
+	for _, c := range cases {
+		env, hdr, err := senderAddress(c.raw, c.name)
+		if err != nil || env != c.envelope || hdr != c.header {
+			t.Fatalf("senderAddress(%q, %q) = %q, %q, %v", c.raw, c.name, env, hdr, err)
+		}
+	}
+}

internal/config/config.go

@@ -37,7 +37,9 @@ type Config struct {
 	SMTPUser string
 	SMTPPass string
 	SMTPFrom string
-	SMTPTLS  bool
+	// SMTPFromName is the sender's display name when SMTP_FROM is a bare address
+	SMTPFromName string
+	SMTPTLS      bool
 	// SMTPSkipVerify accepts self-signed or mismatching certificates (internal mail servers)
 	SMTPSkipVerify bool
 
@@ -220,6 +222,7 @@ func Load() *Config {
 		SMTPUser:               smtpUser,
 		SMTPPass:               smtpPass,
 		SMTPFrom:               smtpFrom,
+		SMTPFromName:           getEnv("SMTP_FROM_NAME", "MindSift"),
 		SMTPTLS:                smtpTLS,
 		SMTPSkipVerify:         smtpSkipVerify,
 		Speech: SpeechConfig{

internal/domain/models.go

@@ -287,9 +287,11 @@ type SystemSettings struct {
 	SMTPUser          string `json:"smtpUser"`
 	// SMTPPass is never sent to the browser (FLAW-34): reads leave it empty and set SMTPPassSet;
 	// writing it empty keeps the stored password
-	SMTPPass       string `json:"smtpPass"`
-	SMTPPassSet    bool   `json:"smtpPassSet,omitempty"`
-	SMTPFrom       string `json:"smtpFrom"`
+	SMTPPass    string `json:"smtpPass"`
+	SMTPPassSet bool   `json:"smtpPassSet,omitempty"`
+	SMTPFrom    string `json:"smtpFrom"`
+	// SMTPFromName is shown as sender when SMTPFrom is a bare address (empty = "MindSift")
+	SMTPFromName   string `json:"smtpFromName"`
 	SMTPTLS        bool   `json:"smtpTls"`
 	SMTPSkipVerify bool   `json:"smtpSkipVerify"` // accept self-signed certificates
 	// AllowPrivateWebhooks lets alarm webhooks reach LAN addresses (and plain http); localhost and cloud

internal/storage/system.go

@@ -92,7 +92,7 @@ func (s *Store) ExportUserData(userID string) (*domain.FullExport, error) {
 
 // --- SYSTEM SETTINGS ---
 
-func (s *Store) SeedSMTPDefaultsFromEnv(host, port, user, pass, from string, tls, skipVerify bool) {
+func (s *Store) SeedSMTPDefaultsFromEnv(host, port, user, pass, from, fromName string, tls, skipVerify bool) {
 	cur, err := s.GetSystemSettings()
 	if err != nil || cur == nil {
 		return
@@ -106,6 +106,7 @@ func (s *Store) SeedSMTPDefaultsFromEnv(host, port, user, pass, from string, tls
 		cur.SMTPUser = strings.TrimSpace(user)
 		cur.SMTPPass = pass
 		cur.SMTPFrom = strings.TrimSpace(from)
+		cur.SMTPFromName = strings.TrimSpace(fromName)
 		cur.SMTPTLS = tls
 		cur.SMTPSkipVerify = skipVerify
 		_ = s.UpdateSystemSettings(cur)
@@ -151,6 +152,8 @@ func (s *Store) GetSystemSettings() (*domain.SystemSettings, error) {
 				settings.SMTPPass = v
 			case "smtp_from":
 				settings.SMTPFrom = v
+			case "smtp_from_name":
+				settings.SMTPFromName = v
 			case "smtp_tls":
 				settings.SMTPTLS = (v != "false" && v != "0")
 			case "smtp_skip_verify":
@@ -212,6 +215,7 @@ func (s *Store) UpdateSystemSettings(settings *domain.SystemSettings) error {
 		('smtp_user', ?),
 		('smtp_pass', ?),
 		('smtp_from', ?),
+		('smtp_from_name', ?),
 		('smtp_tls', ?),
 		('smtp_skip_verify', ?),
 		('allow_private_webhooks', ?),
@@ -227,6 +231,7 @@ func (s *Store) UpdateSystemSettings(settings *domain.SystemSettings) error {
 		strings.TrimSpace(settings.SMTPUser),
 		settings.SMTPPass,
 		strings.TrimSpace(settings.SMTPFrom),
+		strings.TrimSpace(settings.SMTPFromName),
 		tlsStr,
 		skipVerifyStr,
 		privateHooksStr,