SIENTIAPDE-1974-connectors-pi-web-api: Implement OPC UA client certificate handling and update connector security model. Connectors now define security using security.mode and security.policy. Client certificate details (MinIO paths) are fetched from the opc_certificates collection via a MongoDB $lookup and included in the OPC slot. A warning is issued if a connector's client_certificate_id does not resolve to an active client certificate. Documentation (README, CLAUDE.md) and tests have been updated.
vitor-aignosi
0b928a0ea3