[upstream #17033] 17033: MCP server deletion does not fence viewers without an OAuth token #364

Found while reviewing LibreChat-AI#17033 (Codex finding LibreChat-AI#17033 (comment)). cleanupDeletedMCPServerOAuthUsers (packages/api/src/mcp/oauth/cleanup.ts) takes its candidate users from OAuth token holders only and uses the view-ACL snapshot just to filter them. A viewer of a shared database MCP server with no personal OAuth token (server-level credentials) is never fenced or disconnected when the server is deleted, so an already-loaded tool can keep working. The deleteMCPServerController route in api/server/controllers/mcp.js behaves the same way on dev, and account erasure now shares that protocol. Enumerate direct user ACL principals and group members from the snapshot as candidates.