Expose boundary audit logs from workspaces to platform admins #21280
Description
Currently when boundary allows/denies an HTTP request the action is logged within the workspace and visible to the developer only (e.g. Coder Task output). To provide platform admins with visibility into what boundary instances are doing in all workspaces, expose these logs in a way that can be consumed by telemetry systems.
High level plan: aggregate and re-emit these logs in coderd. Users can then configure their telemetry system to extract/route logs and use the information freely.
┌─────────────────────────────────────────────────────────────┐
│ Workspace │
│ ┌──────────┐ Unix Socket ┌─────────────────────┐ │
│ │ Boundary │ ─────────────────► │ Agent (proxy) │ │
│ │ │ /tmp/boundary- │ │ │
│ └──────────┘ audit.sock └──────────┬──────────┘ │
│ │ │
└──────────────────────────────────────────────┼──────────────┘
│ DRPC/Tailnet
▼
┌─────────────┐
│ coderd │
│ (slog emit) │
└─────────────┘
RFC: https://www.notion.so/coderhq/Agent-Boundary-Logs-2afd579be59280f29629fc9823ac41ba