FDN-02/FDN-03/FDN-07/FDN-08: Migrations-Rollback, Objekt-Storage-Interface, go.sum-Fix, Observability

- FDN-02: Rollback-fähige Down-Migrationen (024-026), archivdms seed dev CLI
- FDN-03: internal/objectstore Interface + lokaler WORM-Treiber, signierte Download-URLs
- FDN-07: go.mod/go.sum vervollständigt (fehlender go-ldap/v3-Eintrag), CI-Pipeline (.gitea/workflows/ci.yml, bereits in FDN-01 committet) damit lauffähig
- FDN-08: Request-ID-Middleware, /metrics-Endpoint, Panic-Recovery, Login/Logout/Me technisches Logging inkl. Access-Log je Anfrage

config/config.go

@@ -25,6 +25,10 @@ type APIConfig struct {
 	// TrustedProxies is a list of IP addresses or CIDR ranges whose
 	// X-Forwarded-For header is trusted. Empty = trust no proxy.
 	TrustedProxies []string `yaml:"trusted_proxies"`
+	// MetricsAllowedIPs sind zusätzliche Quell-IPs oder CIDR-Bereiche, die den
+	// unauthentifizierten Prometheus-Endpunkt GET /metrics scrapen dürfen
+	// (FDN-08). Loopback ist immer erlaubt, alles andere per Default gesperrt.
+	MetricsAllowedIPs []string `yaml:"metrics_allowed_ips"`
 }
 
 // ServerConfig holds general server settings.
@@ -101,6 +105,18 @@ type StorageConfig struct {
 	RetentionDays int `yaml:"retention_days"`
 	// MaxUploadSizeMB caps the accepted multipart upload size. 0 = default 50.
 	MaxUploadSizeMB int `yaml:"max_upload_size_mb"`
+	// SignedURLTTLMinutes is the default validity of signed download URLs
+	// (internal/objectstore). 0 = default 15 minutes.
+	SignedURLTTLMinutes int `yaml:"signed_url_ttl_minutes"`
+}
+
+// ResolvedSignedURLTTL returns the configured signed-download-URL validity,
+// falling back to 15 minutes when unset (<= 0).
+func (s StorageConfig) ResolvedSignedURLTTL() time.Duration {
+	if s.SignedURLTTLMinutes <= 0 {
+		return 15 * time.Minute
+	}
+	return time.Duration(s.SignedURLTTLMinutes) * time.Minute
 }
 
 // InboxPath returns the directory raw uploads are written to before hashing