input, macos: initial work on keymapper and macos usage of it

pkg/macos/build.zig

@@ -35,6 +35,7 @@ pub fn link(
         .file = .{ .path = comptime thisDir() ++ "/text/ext.c" },
         .flags = flags.items,
     });
+    step.linkFramework("Carbon");
     step.linkFramework("CoreFoundation");
     step.linkFramework("CoreText");
     return lib;

pkg/macos/foundation/data.zig

@@ -19,6 +19,10 @@ pub const Data = opaque {
     pub fn release(self: *Data) void {
         foundation.CFRelease(self);
     }
+
+    pub fn getPointer(self: *Data) *const anyopaque {
+        return @ptrCast(c.CFDataGetBytePtr(@ptrCast(self)));
+    }
 };
 
 test {