Meta: Create Build/lagom/Root/res with resources for lagom binaries

This way, build files can install things into
`${CMAKE_BINARY_DIR}/Root/res/` and it'll work in both serenity and
lagom builds.

It allows using a single `Core::ResourceImplementation::install()`
call to install both checked-in and generated files (as long as both
get copied into this new build-time staging dir).

No behavior change.

Meta/Lagom/CMakeLists.txt

@@ -418,6 +418,28 @@ if (BUILD_LAGOM_TOOLS)
 endif()
 
 if (BUILD_LAGOM)
+
+    # Create lagom equivalent of Serenity's Build/foo/Root/res (which for Serenity becomes /res in the disk image).
+    # FIXME: Add more files as needed.
+    set(LAGOM_RES "${Lagom_BINARY_DIR}/Root/res")
+    file(MAKE_DIRECTORY "${LAGOM_RES}/fonts")
+    foreach(font
+        LiberationMono-Bold.ttf
+        LiberationMono-BoldItalic.ttf
+        LiberationMono-Italic.ttf
+        LiberationMono-Regular.ttf
+        LiberationSans-Bold.ttf
+        LiberationSans-BoldItalic.ttf
+        LiberationSans-Italic.ttf
+        LiberationSans-Regular.ttf
+        LiberationSerif-Bold.ttf
+        LiberationSerif-BoldItalic.ttf
+        LiberationSerif-Italic.ttf
+        LiberationSerif-Regular.ttf
+        )
+        configure_file("${SERENITY_PROJECT_ROOT}/Base/res/fonts/${font}" "${LAGOM_RES}/fonts/${font}" COPYONLY)
+    endforeach()
+
     # Lagom Libraries
     set(lagom_standard_libraries
         AccelGfx