fetchAndStoreLogPage: walk prev chain to fetch full vault history

includes/utilities.php

@@ -254,18 +254,26 @@ function fetchAndStoreLogPage($pdo, $user, $url) {
         throw new ApiKeyMissingException("User does not have an API key configured.");
     }
 
-    $responseData = executeApiCall($url, USER_KEYS[$user]);
-    validateApiResponse($responseData);
-
     $insertStmt = $pdo->prepare(
         'INSERT INTO vault (id, user, timestamp, description, amount, running_balance) '
         . 'VALUES (:id, :user, :timestamp, :description, :amount, :running_balance) '
-        . 'ON CONFLICT(id) DO NOTHING'
+        . 'ON CONFLICT(id) DO UPDATE SET running_balance = EXCLUDED.running_balance, amount = EXCLUDED.amount'
     );
 
+    do {
+        $responseData = executeApiCall($url, USER_KEYS[$user]);
+        validateApiResponse($responseData);
+
         processLogEntries($responseData['log'], $user, $insertStmt);
 
-    return $responseData['_metadata']['links']['next'] ?? null;
+        // Follow the older-pages chain so the very first call (which gets the
+        // most recent page) also retrieves every older entry. After the prev
+        // chain is exhausted, fall back to the newer-pages chain in case the
+        // caller passed a `from=` URL and the result has a next link.
+        $url = $responseData['_metadata']['links']['prev']
+            ?? $responseData['_metadata']['links']['next']
+            ?? null;
+    } while ($url !== null);
 }
 
 /**