Add MLNDefines.h to make sure Metal backend is available in headers (#3363)

platform/ios/BUILD.bazel

@@ -82,7 +82,17 @@ info_plist(
     base_info_plist = "app/Info.plist",
 )
 
+genrule(
+    name = "mln_defines",
+    outs = ["MLNDefines.h"],
+    cmd = select({
+        "//:metal_renderer": "echo '#define MLN_RENDER_BACKEND_METAL 1' > $@",
+        "//conditions:default": "echo '' > $@",
+    }),
+)
+
 public_hdrs = [
+    ":mln_defines",
     ":ios_public_hdrs",
     ":ios_sdk_hdrs",
     "//platform/darwin:darwin_objc_hdrs",
@@ -123,8 +133,10 @@ apple_xcframework(
     data = glob([
         "resources/*.lproj/**",
         "resources/*.xcassets/**",
+    ]) + [
+        "PrivacyInfo.xcprivacy",
         "resources/metal-cpp-ignores.txt",
-    ]) + ["PrivacyInfo.xcprivacy"],
+    ],
     infoplists = ["info_plist"],
     ios = {
         "simulator": [

platform/ios/CHANGELOG.md

@@ -4,6 +4,10 @@ MapLibre welcomes participation and contributions from everyone. Please read [`M
 
 ## main
 
+## 6.12.3
+
+- add MLNDefines.h to make sure Metal backend is available in headers ([#3335](https://github.com/maplibre/maplibre-native/issues/3335)).
+
 ## 6.12.2
 
 - Strip punctuation from attribution ([#3287](https://github.com/maplibre/maplibre-native/pull/3287)).

platform/ios/VERSION

@@ -1 +1 @@
-6.12.2
+6.12.3