chore(config): upgrade to gosettings v0.4.0

- drop qdm12/govalid dependency
- upgrade qdm12/ss-server to v0.6.0
- do not unset sensitive config settings (makes no sense to me)

internal/configuration/settings/system.go

@@ -2,6 +2,7 @@ package settings
 
 import (
 	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/reader"
 	"github.com/qdm12/gotree"
 )
 
@@ -25,16 +26,10 @@ func (s *System) copy() (copied System) {
 	}
 }
 
-func (s *System) mergeWith(other System) {
-	s.PUID = gosettings.MergeWithPointer(s.PUID, other.PUID)
-	s.PGID = gosettings.MergeWithPointer(s.PGID, other.PGID)
-	s.Timezone = gosettings.MergeWithString(s.Timezone, other.Timezone)
-}
-
 func (s *System) overrideWith(other System) {
 	s.PUID = gosettings.OverrideWithPointer(s.PUID, other.PUID)
 	s.PGID = gosettings.OverrideWithPointer(s.PGID, other.PGID)
-	s.Timezone = gosettings.OverrideWithString(s.Timezone, other.Timezone)
+	s.Timezone = gosettings.OverrideWithComparable(s.Timezone, other.Timezone)
 }
 
 func (s *System) setDefaults() {
@@ -59,3 +54,18 @@ func (s System) toLinesNode() (node *gotree.Node) {
 
 	return node
 }
+
+func (s *System) read(r *reader.Reader) (err error) {
+	s.PUID, err = r.Uint32Ptr("PUID", reader.RetroKeys("UID"))
+	if err != nil {
+		return err
+	}
+
+	s.PGID, err = r.Uint32Ptr("PGID", reader.RetroKeys("GID"))
+	if err != nil {
+		return err
+	}
+
+	s.Timezone = r.String("TZ")
+	return nil
+}