Streaming fails with "Cannot rewind a generator" when stream is re-iterated (PromptJsonDecoder, ReplayedChatMessageIterator)

Applied the fix — replaced foreach with manual valid()/current()/next() iteration in doIterate(). foreach calls rewind() implicitly which crashes on the Partitech SDK's Generator.
Tested with both single and double iteration via drush:

drush php-eval '
  $provider = \Drupal::service("ai.provider")->createInstance("mistral");
  $input = new \Drupal\ai\OperationType\Chat\ChatInput([
    new \Drupal\ai\OperationType\Chat\ChatMessage("user", "Say hello in one sentence"),
  ]);
  $input->setStreamedOutput(TRUE);
  $output = $provider->chat($input, "mistral-small-latest", ["stream"]);
  $n = $output->getNormalized();
  echo "Type: " . get_class($n) . "\n";
  $count = 0;
  foreach ($n as $chunk) { echo $chunk->getText(); $count++; }
  echo "\nChunks: $count\n";
  '

Double iteration (the actual bug scenario — PromptJsonDecoder peeks then ReplayedChatMessageIterator re-iterates):

  drush php-eval '
  $provider = \Drupal::service("ai.provider")->createInstance("mistral");
  $input = new \Drupal\ai\OperationType\Chat\ChatInput([
    new \Drupal\ai\OperationType\Chat\ChatMessage("user", "Say hello in one sentence"),
  ]);
  $input->setStreamedOutput(TRUE);
  $output = $provider->chat($input, "mistral-small-latest", ["stream"]);
  $n = $output->getNormalized();
  echo "=== Pass 1: peek at first 3 chunks ===\n";
  $i = 0;
  foreach ($n as $chunk) { echo "  " . ++$i . ": \"" . $chunk->getText() . "\"\n"; if ($i >= 3) break; }
  echo "=== Pass 2: continue from where left off ===\n";
  $i = 0;
  foreach ($n as $chunk) { echo "  " . ++$i . ": \"" . $chunk->getText() . "\"\n"; }
  echo "Pass 2 chunks: $i\n";
  '

Also tested via AI Explorers, and AI chatbot (non-agent assistant needed for streaming option to show up).

Note that I needed to apply fix from https://www.drupal.org/project/ai/issues/3571925 to make the streaming work in chat and in explorers.