v2.109.0

This release includes several major changes to the proxy's behavior:

- Service profile lookups are now necessary and fundamental to outbound
  discovery for HTTP traffic. That is, if a service profile lookup is
  rejected, endpoint discovery will not be performed; and endpoint
  discovery must succeed for all destinations that are permitted by
  service profiles. This simplifies caching and buffering to reduce
  latency (especially under concurrency).
- Service discovery is now performed for all TCP traffic, and
  connections are balanced over endpoints according to connection
  latency.
- This enables mTLS for **all** meshed connections; not just HTTP.
- Outbound TCP metrics are now hydrated with endpoint-specific labels.