Add subtitles for proof upload in Indonesian and Chinese locales

- Introduced a new subtitle for the proof upload section in both Indonesian and Chinese translation files to enhance user guidance during the refund process.

i18n/locales/id.json

@@ -18,6 +18,7 @@
       "reasonSubtitle": "Refund akan diproses setelah peninjauan resmi",
       "reasonPlaceholder": "Silakan isi...",
       "proofTitle": "Picture proof",
+      "proofSubtitle": "Unggah gambar sebagai bukti",
       "submit": "Kirim refund",
       "toast": {
         "needReason": "Silakan masukkan alasan refund",

i18n/locales/zh.json

@@ -18,6 +18,7 @@
       "reasonSubtitle": "经官方审核后可完成退款",
       "reasonPlaceholder": "请填写...",
       "proofTitle": "Picture proof",
+      "proofSubtitle": "上传图片以提供证据",
       "submit": "提交退款",
       "toast": {
         "needReason": "请填写退款原因",