sapphire: Initial device configuration

Change-Id: I1bbdd196b02bb8db0f4c7aa527e6462ee4807567
Signed-off-by: ReStranger <restranger@disroot.org>
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+Copyright (C) 2025 The LineageOS Project
+
+Device configuration for Xiaomi Redmi Note 13 4G / NFC
+=============================================================
+
+The Xiaomi Redmi Note 13 4G / NFC (codenamed _"sapphire/sapphiren"_) is an mid-range smartphone from Xiaomi.
+
+It was globally released in January 2024.
+
+## Device specifications
+
+Basic   | Spec Sheet
+-------:|:-------------------------
+Platform | Snapdragon® 685 (SM6225)
+RAM & Storage | 6GB/128GB, 8GB/128GB, 8GB/256GB (LPDDR4X RAM, UFS 2.2 storage)
+Shipped Android Version | 13
+Battery | Non-removable, 5000 mAh
+Display | 6.67″, 120Hz, 2400x1080 (395 ppi)
+Rear camera | 108MP wide angle, 8MP ultra wide-angle, 2MP macro
+Front camera | 16MP in-display
+
+## Device picture
+
+![Xiaomi Redmi Note 13 4G](https://i02.appmifile.com/282_operator_sg/02/01/2024/3ed59552a4950465a43d4f3f9598d8b4.png "Xiaomi Redmi Note 13 4G in black, blue, gold and green")