feat: Update API versioning and parser handling for improved schedule updates and error management

android/app/src/main/kotlin/org/xtimms/psu/schedule/data/Api.kt

@@ -22,8 +22,11 @@ import java.util.concurrent.TimeUnit
  */
 class ApiException(message: String, val offline: Boolean = false, val code: String? = null) : Exception(message)
 
-/** Server codes after which trying again later can help. */
-private val SOURCE_DOWN = setOf("source_unavailable", "source_timeout", "busy")
+/**
+ * Server codes after which trying again later can help: the university is down or slow, the
+ * server is busy or did not answer in time, or this address sent too many requests.
+ */
+private val SOURCE_DOWN = setOf("source_unavailable", "source_timeout", "busy", "timeout", "too_many_requests")
 
 val json = Json {
     ignoreUnknownKeys = true