Use shared preference to store forwarding ports

key PREFERENCE_FORWARDING_PORTS for all available ports (StringSet)
key PREFERENCE_FORWARDING_PORT_IS_ENABLED_{port} for the enable/disable
of ports (Boolean)

Bug: 375873420
Test: Manually
Change-Id: I06b360d6d31cc34a6618fc418f7fdeef13694ccf
diff --git a/android/TerminalApp/res/values/config.xml b/android/TerminalApp/res/values/config.xml
index 055abb7..9d2456c 100644
--- a/android/TerminalApp/res/values/config.xml
+++ b/android/TerminalApp/res/values/config.xml
@@ -18,4 +18,6 @@
     <string name="preference_file_key" translatable="false">com.android.virtualization.terminal.PREFERENCE_FILE_KEY</string>
     <string name="preference_disk_size_key" translatable="false">PREFERENCE_DISK_SIZE_KEY</string>
     <string name="preference_min_disk_size_key" translatable="false">PREFERENCE_MIN_DISK_SIZE_KEY</string>
+    <string name="preference_forwarding_ports" translatable="false">PREFERENCE_FORWARDING_PORTS</string>
+    <string name="preference_forwarding_port_is_enabled" translatable="false">PREFERENCE_FORWARDING_PORT_IS_ENABLED_</string>
 </resources>
\ No newline at end of file