fix(modules): add META-INF for Magisk versions before v28

Magisk before v28 requires META-INF/com/google/android/update-binary
+ updater-script in module zips to extract them; without these the
manager fails with an unpack error (issue #23). Magisk v28+ removed
this requirement, which is why the bug only shows up on older managers.

Added the standard Magisk template (same one already used by the
zygisk module) to portshide and kmod. CI's `(cd module && zip -qr)`
step picks up the new files automatically.

kmod/module/META-INF/com/google/android/update-binary

@@ -0,0 +1,23 @@
+#!/sbin/sh
+# KernelSU-Next / Magisk module installer entry point.
+umask 022
+ui_print() { echo "$1"; }
+require_new_magisk() {
+  ui_print "*******************************"
+  ui_print " Please install KernelSU-Next"
+  ui_print " or Magisk v20.4+"
+  ui_print "*******************************"
+  exit 1
+}
+OUTFD=$2
+ZIPFILE=$3
+mount /data 2>/dev/null
+[ -f /data/adb/magisk/util_functions.sh ] || [ -f /data/adb/ksu/util_functions.sh ] || require_new_magisk
+if [ -f /data/adb/magisk/util_functions.sh ]; then
+    . /data/adb/magisk/util_functions.sh
+    [ $MAGISK_VER_CODE -lt 20400 ] && require_new_magisk
+else
+    . /data/adb/ksu/util_functions.sh
+fi
+install_module
+exit 0

kmod/module/META-INF/com/google/android/updater-script

@@ -0,0 +1 @@
+#MAGISK