docs: PZERO custom OpenAI endpoint (not MCP)

[cursor]

LibreChat already supports custom OpenAI-compatible endpoints. Issue 738 is the hosted MCP connector. This request is the chat completions path: a named PZERO baseURL example so users do not mix MCP and HTTP.

endpoints:
  custom:
    - name: "PZERO"
      apiKey: "${PZERO_API_KEY}"
      baseURL: "https://api.pzero.studio/v1"
      models:
        default: ["deepseek-v4-flash"]
        fetch: true
      titleConvo: true
      modelDisplayLabel: "PZERO"

baseURL is the /v1 root. fetch: true can use the public GET /v1/models catalog. Chat still needs a funded pzero_ key.

Get a key: https://pzero.studio/agents (sign-in free; min top-up 1 USDC on Base; no starter credits).

I am not asking for a first-party LibreChat plugin. Custom endpoints are the existing seam.

Every AI Credit is at least 20% off $1 list. Usage is paid. Do not start implementation on my behalf until the board says Ready; the YAML is for users today.

Related MCP issue (different surface): #738