OpenAI Chat node and execution analytics

GPT-4.1 and GPT-4o families land in the Text node. A new analytics dashboard tracks per-flow runs, latency, and token spend.

• NewOpenAI Chat node

  GPT-4o, GPT-4o Mini, GPT-4.1, GPT-4.1 Mini, and GPT-4.1 Nano available in the Text node.

• NewExecution analytics dashboard

  Per-flow run counts, success rate, p50/p95 latency, and token spend.