Ensure ankihelper is rebuilt on arch change

https://forums.ankiweb.net/t/24-04-breaks-dark-mode-on-mac/43048

build/configure/src/aqt.rs

@@ -347,6 +347,7 @@ fn build_macos_helper(build: &mut Build) -> Result<()> {
                 inputs: hashmap! {
                     "script" => inputs!["qt/mac/helper_build.py"],
                     "in" => inputs![glob!["qt/mac/*.swift"]],
+                    "" => inputs!["out/env"],
                 },
                 outputs: hashmap! {
                     "out" => vec!["qt/_aqt/data/lib/libankihelper.dylib"],

qt/mac/helper_build.py

@@ -1,6 +1,7 @@
 # Copyright: Ankitects Pty Ltd and contributors
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+import os
 import platform
 import subprocess
 import sys
@@ -10,7 +11,7 @@ out_dylib, *src_files = sys.argv[1:]
 out_dir = Path(out_dylib).parent.resolve()
 src_dir = Path(src_files[0]).parent.resolve()
 
-if platform.machine() == "arm64":
+if platform.machine() == "arm64" and not os.environ.get("MAC_X86"):
     target = "arm64-apple-macos11"
 else:
     target = "x86_64-apple-macos10.14"