fix: prevent autoping disable on false negative ping support check

Remove autodisable logic (prefs_set_autoping(0)) and early return in autoping
to treat intermittent false negatives from connection_supports(XMPP_FEATURE_PING).
Add one-time error display with debug features print for monitoring; warn on first failing
check without aborting to maintain functionality while investigating root cause.

src/xmpp/connection.c

@@ -979,6 +979,7 @@ _connection_handler(xmpp_conn_t* const xmpp_conn, const xmpp_conn_event_t status
 
         connection_get_jid();
         conn.domain = strdup(conn.jid->domainpart);
+        log_debug("conn.domain=%s", conn.jid->domainpart);
 
         connection_clear_data();
         conn.features_by_jid = g_hash_table_new_full(g_str_hash, g_str_equal, free, (GDestroyNotify)g_hash_table_destroy);
@@ -1163,3 +1164,32 @@ connection_get_profanity_identifier(void)
 {
     return prof_identifier;
 }
+
+void
+connection_debug_print_features()
+{
+    log_debug("=== Connection Features ===");
+
+    GHashTableIter iter;
+    gpointer jid_ptr, features_ptr;
+
+    g_hash_table_iter_init(&iter, conn.features_by_jid);
+    while (g_hash_table_iter_next(&iter, &jid_ptr, &features_ptr)) {
+        const char* jid = (const char*)jid_ptr;
+        GHashTable* features = (GHashTable*)features_ptr;
+
+        if (!features || g_hash_table_size(features) == 0) {
+            log_debug("%s:\t(no features)", jid);
+            continue;
+        }
+
+        GList* feature_keys = g_hash_table_get_keys(features);
+        for (GList* l = feature_keys; l != NULL; l = l->next) {
+            const char* feature = (const char*)l->data;
+            log_debug("%s:\t%s", jid, feature);
+        }
+        g_list_free(feature_keys);
+    }
+
+    log_debug("=== End of Features ===");
+}