Per-assistant Slack onboarding, risk-only trace filtering, and resilience fixes

This release adds a per-assistant Slack setup card with capability and event selection, brings a risk-only toggle to trace panels, and ships a batch of resilience fixes around model completions, OAuth metadata, and remote session scoping.

Features

• Per-assistant Slack setup with tuned warm runtimes #3063  - A new Slack setup card lets operators pick capabilities (send, read, react, and more) and which events wake the assistant up, then provisions a dedicated per-assistant Slack toolset instead of reusing a shared one. The card warns about always-on event firehoses, and the onboarding agent offers plain-English filter narrowing after Slack install. New assistants now default to five concurrent warm runtimes and a 60-second warm TTL so they handle bursts without queueing while reclaiming idle resources faster. (Author: @danielkov )
• Risk-only trace filter #3121  - Adds a risk-only toggle to trace panels and deep-linked Risk Events that open with risk filtering enabled. (Author: @alx-xo )

Bug fixes

• Retry empty model completions #3129  - Retries chat completions when the upstream model returns an empty response and reports the upstream details when it still fails, reducing transient playground and chat errors. (Author: @danielkov )
• Project-scoped Remote OAuth client lookups #3090  - Remote OAuth client lookups no longer surface clients whose bound user session issuer lives in a different project or has been soft-deleted. The legacy fallback path now scopes both the client and its user session issuer to the request’s project and excludes soft-deleted records, matching the join-table read path. (Author: @walker-tx )
• OAuth metadata resolved via mcp_endpoints #3118  - Resolves /mcp well-known OAuth metadata via mcp_endpoints with a toolset fallback. (Author: @bflad )
• Codex telemetry hooks routed through a wrapper #3116  - Routes telemetry-only Codex observability hooks through a shell background wrapper instead of Codex’s unsupported async hook flag. (Author: @danielkov )