Sponsor badges for everyone + new app icon

- Sponsor checkmark now shows on ANY user's profile, not just your own
- SponsorHelper batches sponsor-status lookups by Telegram id (cached 6h)
  and posts sponsorStatusUpdated so the badge redraws when resolved
- ProfileActivity requests the lookup when opening a profile
- Replace the main launcher icon with foxigram4.png (all densities,
  legacy + adaptive foreground)

TMessagesProj/src/main/java/org/telegram/ui/ProfileActivity.java

@@ -11359,6 +11359,9 @@ public class ProfileActivity extends BaseFragment implements NotificationCenter.
         if (avatarContainer == null || nameTextView == null || getParentActivity() == null) {
             return;
         }
+        if (userId != 0) {
+            SponsorHelper.requestSponsorStatus(userId);
+        }
         String onlineTextOverride;
         int currentConnectionState = getConnectionsManager().getConnectionState();
         if (currentConnectionState == ConnectionsManager.ConnectionStateWaitingForNetwork) {
@@ -11568,7 +11571,7 @@ public class ProfileActivity extends BaseFragment implements NotificationCenter.
                     } else if (getMessagesController().isDialogMuted(dialogId != 0 ? dialogId : userId, topicId)) {
                         nameTextView[a].setRightDrawable2(getThemedDrawable(Theme.key_drawable_muteIconDrawable));
                         nameTextViewRightDrawable2ContentDescription = LocaleController.getString(R.string.NotificationsMuted);
-                    } else if (user.self && SponsorHelper.isSponsor(user.id)) {
+                    } else if (SponsorHelper.isKnownSponsor(user.id)) {
                         rightIconIsSponsor = true;
                         nameTextView[a].setRightDrawable2(getFoxSponsorDrawable(a));
                         nameTextViewRightDrawable2ContentDescription = LocaleController.getString(R.string.FoxSponsorBadge);
@@ -11595,7 +11598,7 @@ public class ProfileActivity extends BaseFragment implements NotificationCenter.
                         nameTextView[a].setRightDrawable2(getScamDrawable(user.scam ? 0 : 1));
                     } else if (user.verified) {
                         nameTextView[a].setRightDrawable2(getVerifiedCrossfadeDrawable(a));
-                    } else if (user.self && SponsorHelper.isSponsor(user.id)) {
+                    } else if (SponsorHelper.isKnownSponsor(user.id)) {
                         rightIconIsSponsor = true;
                         nameTextView[a].setRightDrawable2(getFoxSponsorDrawable(a));
                     } else {

TMessagesProj/src/main/java/tw/nekomimi/nekogram/helpers/SponsorHelper.java

@@ -15,7 +15,11 @@ import java.io.InputStream;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * Resolves the "sponsor" status of the current Telegram user against the
@@ -43,6 +47,16 @@ public final class SponsorHelper {
 
     private static volatile boolean checking = false;
 
+    // ─── Per-user sponsor cache (for showing badges of OTHER users) ───
+    // Cached sponsor flag per Telegram id, with a freshness timestamp.
+    private static final ConcurrentHashMap<Long, Boolean> otherSponsor = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<Long, Long> otherChecked = new ConcurrentHashMap<>();
+    // Ids waiting to be resolved in the next batch request.
+    private static final Set<Long> pendingLookup = new LinkedHashSet<>();
+    private static volatile boolean lookupScheduled = false;
+    // Re-check another user's status at most once every 6 hours.
+    private static final long OTHER_TTL_MS = 6 * 60 * 60 * 1000L;
+
     private static SharedPreferences prefs() {
         return ApplicationLoader.applicationContext.getSharedPreferences(PREFS, android.content.Context.MODE_PRIVATE);
     }
@@ -61,6 +75,144 @@ public final class SponsorHelper {
         return user != null && isSponsor(user.id);
     }
 
+    /**
+     * Sponsor flag for ANY Telegram user id (not just the current account).
+     * Combines the locally-stored value for the current account with the
+     * per-user cache populated by {@link #requestSponsorStatus(long)}. Returns
+     * the best known answer synchronously; callers should also invoke
+     * {@link #requestSponsorStatus(long)} to keep the cache warm and get a
+     * {@link NotificationCenter#sponsorStatusUpdated} when it changes.
+     */
+    public static boolean isKnownSponsor(long telegramId) {
+        if (telegramId == 0) {
+            return false;
+        }
+        // The current account's own status is authoritative from /mobile/me.
+        var self = UserConfig.getInstance(UserConfig.selectedAccount).getCurrentUser();
+        if (self != null && self.id == telegramId) {
+            return isSponsor(telegramId);
+        }
+        Boolean cached = otherSponsor.get(telegramId);
+        return cached != null && cached;
+    }
+
+    /**
+     * Ask the backend whether {@code telegramId} is a sponsor. Self-throttles
+     * per id and batches concurrent requests. Posts
+     * {@link NotificationCenter#sponsorStatusUpdated} when a value changes so
+     * the UI can redraw the badge.
+     */
+    public static void requestSponsorStatus(long telegramId) {
+        if (telegramId == 0) {
+            return;
+        }
+        var self = UserConfig.getInstance(UserConfig.selectedAccount).getCurrentUser();
+        if (self != null && self.id == telegramId) {
+            return; // covered by refresh()/mobile-me
+        }
+        Long last = otherChecked.get(telegramId);
+        if (last != null && Math.abs(System.currentTimeMillis() - last) < OTHER_TTL_MS) {
+            return;
+        }
+        synchronized (pendingLookup) {
+            pendingLookup.add(telegramId);
+            if (lookupScheduled) {
+                return;
+            }
+            lookupScheduled = true;
+        }
+        // Small delay so several visible rows coalesce into one request.
+        AndroidUtilities.runOnUIThread(() -> Utilities.globalQueue.postRunnable(SponsorHelper::flushLookup), 250);
+    }
+
+    // @WorkerThread
+    private static void flushLookup() {
+        List<Long> batch;
+        synchronized (pendingLookup) {
+            lookupScheduled = false;
+            if (pendingLookup.isEmpty()) {
+                return;
+            }
+            batch = new ArrayList<>(pendingLookup);
+            pendingLookup.clear();
+        }
+        if (batch.size() > 200) {
+            batch = batch.subList(0, 200);
+        }
+        StringBuilder ids = new StringBuilder();
+        for (int i = 0; i < batch.size(); i++) {
+            if (i > 0) {
+                ids.append(',');
+            }
+            ids.append(batch.get(i));
+        }
+
+        HttpURLConnection connection = null;
+        try {
+            URL url = new URL(BASE_URL + "/api/auth/mobile/sponsors/by-telegram?ids=" + ids);
+            connection = (HttpURLConnection) url.openConnection();
+            connection.setInstanceFollowRedirects(true);
+            connection.setConnectTimeout(15000);
+            connection.setReadTimeout(15000);
+            connection.setRequestProperty("Accept", "application/json");
+
+            int code = connection.getResponseCode();
+            if (code != HttpURLConnection.HTTP_OK) {
+                FileLog.d(TAG + ": sponsors/by-telegram returned HTTP " + code);
+                return;
+            }
+
+            StringBuilder sb = new StringBuilder();
+            try (InputStream in = connection.getInputStream()) {
+                byte[] buffer = new byte[4096];
+                int read;
+                while ((read = in.read(buffer)) >= 0) {
+                    sb.append(new String(buffer, 0, read, "UTF-8"));
+                }
+            }
+
+            JSONObject json = new JSONObject(sb.toString());
+            if (!json.optBoolean("success", false)) {
+                return;
+            }
+            Set<Long> sponsors = new HashSet<>();
+            JSONArray arr = json.optJSONArray("sponsors");
+            if (arr != null) {
+                for (int i = 0; i < arr.length(); i++) {
+                    sponsors.add(arr.optLong(i));
+                }
+            }
+
+            boolean changed = false;
+            long now = System.currentTimeMillis();
+            for (Long id : batch) {
+                boolean isSponsor = sponsors.contains(id);
+                Boolean prev = otherSponsor.put(id, isSponsor);
+                otherChecked.put(id, now);
+                if (prev == null || prev != isSponsor) {
+                    changed = true;
+                }
+            }
+            if (changed) {
+                AndroidUtilities.runOnUIThread(() ->
+                        NotificationCenter.getGlobalInstance().postNotificationName(NotificationCenter.sponsorStatusUpdated));
+            }
+        } catch (Exception e) {
+            FileLog.e(e);
+        } finally {
+            if (connection != null) {
+                connection.disconnect();
+            }
+            // If more ids queued up while we were busy, schedule another pass.
+            synchronized (pendingLookup) {
+                if (!pendingLookup.isEmpty() && !lookupScheduled) {
+                    lookupScheduled = true;
+                    Utilities.globalQueue.postRunnable(SponsorHelper::flushLookup, 250);
+                }
+            }
+        }
+    }
+
     /**
      * Whether the given Telegram id is linked to a FoxCloud/GhostCloud account.
      * Only meaningful after at least one successful {@link #refresh(boolean)}.