[llama-index] support for llamaindex tags

[mikeldking]

Of interest to arize, we just merged/released an interesting update to instrumentation
Basically, users can add arbitrary tags to their spans/events
from llama_index.core.instrumentation.dispatcher import instrument_tags

with instrument_tags({"user_id": 1234}):
  agent.chat("Hello!")

Any events/spans emitted under the with block will have a .tags attribute with the provided tags

[dosubot]

Hi, @mikeldking. I'm Dosu, and I'm helping the OpenInference team manage their backlog. I'm marking this issue as stale.

Issue Summary

• You requested support for arbitrary tags to spans/events in the llama-index.
• The functionality has been updated to allow custom tags using the instrument_tags function.
• No further comments or developments have been made on this issue.

Next Steps

• Please confirm if this issue is still relevant to the latest version of the OpenInference repository. If so, you can keep the discussion open by commenting on the issue.
• Otherwise, this issue will be automatically closed in 7 days.

Thank you for your understanding and contribution!