fix: nextAppOpModeInCycle non-static for Java 8 source compatibility

The release.yml workflow failed on tag v0.4.1 because Java 8 source
compatibility (sourceCompatibility/targetCompatibility VERSION_1_8 in
app/build.gradle) doesn't allow static members inside inner classes.
The helper added in 07e42d9 was declared static inside
AppDetailsRecyclerAdapter and broke compileReleaseJavaWithJavac:

  AppDetailsPermissionsFragment.java:558: error: Illegal static
  declaration in inner class
  AppDetailsPermissionsFragment.AppDetailsRecyclerAdapter

Demoted to a non-static private method on the inner class. Touches no
instance state, so behavior is identical.

Local-built APK (versionCode 5 / versionName 0.4.1) installs cleanly
on Samsung S25 Ultra and is signed with the release cert
SHA-256 21:5F:B4:70:63:2E:A6:CD:59:A4:BA:AB:35:0A:9E:0B:99:AD:11:0F:DD:FA:F5:A9:EA:64:61:E5:D0:C2:38:6C.

Author: SysAdminDoc

app/src/main/java/io/github/muntashirakon/AppManager/details/AppDetailsPermissionsFragment.java

@@ -553,9 +553,12 @@ public int getItemCount() {
          * Cycle ALLOWED → IGNORED → ERRORED → ALLOWED for the row-tap toggle. Any
          * other current mode (FOREGROUND, DEFAULT, etc.) re-enters the cycle at
          * ALLOWED so the user always lands on a known three-state ladder.
+         *
+         * <p>Non-static because Java 8 source compatibility forbids static
+         * members inside inner classes. No instance state is touched.
          */
         @AppOpsManagerCompat.Mode
-        private static int nextAppOpModeInCycle(@AppOpsManagerCompat.Mode int currentMode) {
+        private int nextAppOpModeInCycle(@AppOpsManagerCompat.Mode int currentMode) {
             switch (currentMode) {
                 case android.app.AppOpsManager.MODE_ALLOWED:
                     return android.app.AppOpsManager.MODE_IGNORED;