Allow users to disable terminal margin adjustment from termux settings

Previously in (32135025) support was added with `disable-terminal-margin-adjustment` `termux.properties` property to disable terminal margin adjustment in case in causes screen flickering or other issues on some devices. It has now been removed in (7aefd943) and moved to Termux Settings since if it causes issues at startup and users can't access `termux.properties` file from the terminal, they will have to use SAF or root to access it, which will require an external app.

Users can set the value from the `Termux Settings` -> `Termux` -> `Terminal View` -> `Terminal Margin Adjustment` toggle. The `Termux Settings` can be accessed from left drawer in termux and from the android launcher shortcut for Termux Settings, usually accessible by long holding on Termux icon.

app/src/main/java/com/termux/app/TermuxActivity.java

@@ -259,7 +259,8 @@ public final class TermuxActivity extends Activity implements ServiceConnection
         if (mTermuxTerminalViewClient != null)
             mTermuxTerminalViewClient.onStart();
 
-        addTermuxActivityRootViewGlobalLayoutListener();
+        if (mPreferences.isTerminalMarginAdjustmentEnabled())
+            addTermuxActivityRootViewGlobalLayoutListener();
 
         registerTermuxActivityBroadcastReceiver();
     }

app/src/main/java/com/termux/app/fragments/settings/termux/TerminalViewPreferencesFragment.java

@@ -0,0 +1,77 @@
+package com.termux.app.fragments.settings.termux;
+
+import android.content.Context;
+import android.os.Bundle;
+
+import androidx.annotation.Keep;
+import androidx.preference.PreferenceDataStore;
+import androidx.preference.PreferenceFragmentCompat;
+import androidx.preference.PreferenceManager;
+
+import com.termux.R;
+import com.termux.shared.settings.preferences.TermuxAppSharedPreferences;
+
+@Keep
+public class TerminalViewPreferencesFragment extends PreferenceFragmentCompat {
+
+    @Override
+    public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
+        Context context = getContext();
+        if (context == null) return;
+
+        PreferenceManager preferenceManager = getPreferenceManager();
+        preferenceManager.setPreferenceDataStore(TerminalViewPreferencesDataStore.getInstance(context));
+
+        setPreferencesFromResource(R.xml.termux_terminal_view_preferences, rootKey);
+    }
+
+}
+
+class TerminalViewPreferencesDataStore extends PreferenceDataStore {
+
+    private final Context mContext;
+    private final TermuxAppSharedPreferences mPreferences;
+
+    private static TerminalViewPreferencesDataStore mInstance;
+
+    private TerminalViewPreferencesDataStore(Context context) {
+        mContext = context;
+        mPreferences = TermuxAppSharedPreferences.build(context, true);
+    }
+
+    public static synchronized TerminalViewPreferencesDataStore getInstance(Context context) {
+        if (mInstance == null) {
+            mInstance = new TerminalViewPreferencesDataStore(context);
+        }
+        return mInstance;
+    }
+
+
+
+    @Override
+    public void putBoolean(String key, boolean value) {
+        if (mPreferences == null) return;
+        if (key == null) return;
+
+        switch (key) {
+            case "terminal_margin_adjustment":
+                    mPreferences.setTerminalMarginAdjustment(value);
+                break;
+            default:
+                break;
+        }
+    }
+
+    @Override
+    public boolean getBoolean(String key, boolean defValue) {
+        if (mPreferences == null) return false;
+
+        switch (key) {
+            case "terminal_margin_adjustment":
+                return mPreferences.isTerminalMarginAdjustmentEnabled();
+            default:
+                return false;
+        }
+    }
+
+}