Update stacklok/toolhive to v0.28.2 (#895)

* Update stacklok/toolhive to v0.28.2

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

* Refresh reference assets for toolhive v0.28.2

---------

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/upstream-projects.yaml

@@ -35,7 +35,7 @@ projects:
 
   - id: toolhive
     repo: stacklok/toolhive
-    version: v0.28.1
+    version: v0.28.2
     # toolhive is a monorepo covering the CLI, the Kubernetes
     # operator, and the vMCP gateway. It also introduces cross-
     # cutting features that land in concepts/, integrations/,

docs/toolhive/reference/cli/thv_registry_login.md

@@ -32,6 +32,7 @@ thv registry login [flags]
 ### Options
 
 ```
+  -p, --allow-private-ip   Allow --registry to reference a private IP address (default false). Mirrors the flag on 'thv config set-registry'.
       --audience string    OAuth audience parameter for registry authentication (optional)
       --client-id string   OAuth client ID for registry authentication
   -h, --help               help for login