sys: wrap log methods

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/app/app_stub_test.go

@@ -3,6 +3,7 @@ package app_test
 import (
 	"fmt"
 	"io/fs"
+	"log"
 	"os/user"
 	"strconv"
 
@@ -23,6 +24,9 @@ func (s *stubNixOS) Exit(code int)                            { panic("called ex
 func (s *stubNixOS) EvalSymlinks(path string) (string, error) { return path, nil }
 func (s *stubNixOS) Uid(aid int) (int, error)                 { return 1000000 + 0*10000 + aid, nil }
 
+func (s *stubNixOS) Println(v ...any)               { log.Println(v...) }
+func (s *stubNixOS) Printf(format string, v ...any) { log.Printf(format, v...) }
+
 func (s *stubNixOS) LookupEnv(key string) (string, bool) {
 	switch key {
 	case "SHELL":