Add ToolReferenceChunk, ToolFileChunk, BuiltInConnector enum,
ReferenceID union type (int|string), GuardrailConfig with v1/v2
moderation, ConnectorTool for custom connectors, and guardrails
field on chat/agents/conversation requests.
Add AudioTranscriptionRealtime and AudioSpeech to ModelCapabilities.
Move GuardrailConfig from agents/ to chat/ as shared base type.
Remove bundled OpenAPI spec; SDK now tracks upstream Python SDK.
BREAKING: ReferenceChunk.ReferenceIDs changed from []int to
[]ReferenceID. Use IntRef(n) / StringRef(s) constructors.
vikingowl
52231df17b