fix: Add jsonschema dependency for Agent Builder config validation

Close #3494

Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 832362832

Author: GWeale

pyproject.toml

@@ -43,6 +43,7 @@ dependencies = [
   "google-cloud-storage>=3.0.0, <4.0.0",                     # For GCS Artifact service
   "google-genai>=1.45.0, <2.0.0",                            # Google GenAI SDK
   "graphviz>=0.20.2, <1.0.0",                                # Graphviz for graph rendering
+  "jsonschema>=4.23.0, <5.0.0",                              # Agent Builder config validation
   "mcp>=1.8.0, <2.0.0;python_version>='3.10'",               # For MCP Toolset
   "opentelemetry-api>=1.37.0, <=1.37.0",                     # OpenTelemetry - limit upper version for sdk and api to not risk breaking changes from unstable _logs package.
   "opentelemetry-exporter-gcp-logging>=1.9.0a0, <2.0.0",