build(hosting): declare microsoft-agents-a365-runtime as a direct dependency

The hosting token cache now imports get_observability_authentication_scope
from microsoft-agents-a365-runtime. It was only available transitively through
observability-core; declare it directly so the published metadata matches the
imports. The build pins it to the same version like other internal packages.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot-Session: 5cbf5f6b-cc40-4b7e-a591-65848db73a12

Author: DheerajPannala

libraries/microsoft-agents-a365-observability-hosting/pyproject.toml

@@ -27,6 +27,7 @@ keywords = ["observability", "telemetry", "tracing", "opentelemetry", "monitorin
 dependencies = [
     "microsoft-agents-hosting-core",
     "microsoft-agents-a365-observability-core",
+    "microsoft-agents-a365-runtime",
     "opentelemetry-api",
 ]