AI Agent: Allow clients to query errored Open API requests

🔍 Problem Statement

As a client admin, I can only find errored API requests by searching Settings > Logs > Open API by hand, which results in avoidable support tickets.

💡 User Story

• As a client admin, I want to ask the Pelcro AI Agent for errored API requests by customer, endpoint, response code or date, so that I can diagnose failures without contacting support.

🎯 Definition of Done (DoD)

• Given a site with errored Open API requests (4xx or 5xx), when an admin calls [clarify endpoint, e.g. GET /api/v1/core/logs/open-api] with a date range, then it returns only that site's errored requests.

• Given filters (customer ID, request URI, response code, report_id), when applied, then each result matches them and shows the timestamp, request URI, response code, error and customer ID.

• Given an admin asks the AI Agent "show 422 errors from the last 7 days", when it answers, then it lists the matching requests and their total count.

• Given a user without the admin role, when they ask the AI Agent or call the endpoint, then the request is refused.

• Given the release, then the endpoint is documented on docs.pelcro.com and covered by automated tests, and it is exposed as an MCP tool with at least one eval.

• This change will impact the API and Integration layers, specifically a new Core API logs endpoint, a new MCP server tool and the AI Agent (/admin/ai-agent/chat).

• This solution will include the following limitations: read-only; errored Open API requests only, no successful requests; no real-time alerts; no errors from custom client UI flows or from payments the gateway rejects before they reach Pelcro; history limited to log retention [clarify]; request payloads excluded [clarify].