feat(openai): add tags & metadata at the call level

[Dam-Buty]

This adds the possibility to add tags/metadata to the OpenAI instrumentation, at the call level. The original feature (at the instrumentation level) is retained.

This is meant to be used like so :

const instrumentedOpenAi = client.instrumentation.openai();

await instrumentedOpenAi.chat.completions.create(
  {
    model: 'gpt-3.5-turbo',
    messages: [
      { role: 'system', content: 'You are a helpful assistant.' },
      { role: 'user', content: 'What is the capital of Canada?' }
    ]
  },
  {
    literalaiTags: ['tag3', 'tag4'],
    literalaiMetadata: { otherKey: 'otherValue' }
  }
);

[linear[bot]]

ENG-1685 add metadata support to generations