refactor: move wallpaper.cache to 0:/state

kernel/src/Api/BuildNo.hpp

@@ -12,4 +12,4 @@
 
 #pragma once
 
-#define MONTAUK_BUILD_NUMBER 3
+#define MONTAUK_BUILD_NUMBER 4

kernel/src/Fs/ProtectedPaths.cpp

@@ -29,9 +29,13 @@ namespace Fs {
         {"/config/ssh.toml",         false, montauk::abi::CAP_USER_ADMIN},
         {"/config/capabilities.toml",false, montauk::abi::CAP_USER_ADMIN},
         {"/config/consent.toml",     false, montauk::abi::CAP_USER_ADMIN},
-        {"/config/wallpaper.cache",  false, montauk::abi::CAP_USER_ADMIN},
         // Read by the Bluetooth driver at controller bring-up.
         {"/config/bluetooth.toml",   false, montauk::abi::CAP_DEVICE_ADMIN},
+        // Login's wallpaper cache. The directory is listed for the same reason
+        // as /config: a rename only checks its own path, so an unlisted parent
+        // could be swapped for one holding a forged cache.
+        {"/state/cache",             false, montauk::abi::CAP_USER_ADMIN},
+        {"/state/cache/wallpaper.cache", false, montauk::abi::CAP_USER_ADMIN},
         {"/apps",                    true,  montauk::abi::CAP_SYSTEM_IMAGE},
         {"/os",                      true,  montauk::abi::CAP_SYSTEM_IMAGE},
     };