Added a feature to save logs to local storage (#1741)

- Added export logs to local storage
[1664](https://github.com/tiann/KernelSU/issues/1664)

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Co-authored-by: weishu <twsxtd@gmail.com>

manager/app/src/main/res/values-da/strings.xml

@@ -79,4 +79,5 @@
     <string name="profile_selinux_rules">Regler</string>
     <string name="restart_app">Genstart</string>
     <string name="require_kernel_version">Den nuværende KernelSU version %d er for lav til manageren for at fungere ordentligt. Opgrader til version %d eller højere!</string>
+    <string name="save_log">Gem Logfiler</string>
 </resources>