linux: get build working with new system

src/core/Linux.zig

@@ -25,11 +25,17 @@ const BackendEnum = enum {
     x11,
     wayland,
 };
+
 const Backend = union(BackendEnum) {
     x11: X11,
     wayland: Wayland,
 };
 
+pub const Native = union(BackendEnum) {
+    x11: X11.Native,
+    wayland: Wayland.Native,
+};
+
 pub const Linux = @This();
 
 allocator: std.mem.Allocator,
@@ -52,6 +58,10 @@ backend: Backend,
 const MISSING_FEATURES_X11 = [_][]const u8{ "Resizing window", "Changing display mode", "VSync", "Setting window border/cursor" };
 const MISSING_FEATURES_WAYLAND = [_][]const u8{ "Changing display mode", "VSync", "Setting window border/cursor" };
 
+pub fn tick(core: *Core) !void {
+    _ = core;
+}
+
 pub fn init(
     linux: *Linux,
     core: *Core,

src/core/linux/Wayland.zig

@@ -70,6 +70,8 @@ libxkbcommon: LibXkbCommon,
 modifiers: Core.KeyMods,
 modifier_indices: KeyModInd,
 
+pub const Native = struct {};
+
 pub fn init(
     linux: *Linux,
     core: *Core,

src/core/linux/X11.zig

@@ -61,6 +61,8 @@ cursors: [@typeInfo(CursorShape).@"enum".fields.len]?c.Cursor,
 // Mutable state fields; read/write by any thread
 surface_descriptor: *gpu.Surface.DescriptorFromXlibWindow,
 
+pub const Native = struct {};
+
 pub fn init(
     linux: *Linux,
     core: *Core,