default to any if type not found in schema

[wjayesh]

Fix: Support Pydantic Any fields in function signature generation

Summary:
Previously, function_signature_from_jsonschema would error if a property schema lacked a type field (which happens for typing.Any in Pydantic). This PR treats such cases as typing.Any, matching JSON Schema and Pydantic intent.

Risks & Safety:

• ✅ Semantically correct: JSON Schema omitting type = "any type allowed" → Any
• ✅ Only affects previously failing cases (e.g., flexible API fields)
• ✅ Type safety is preserved for all typed fields
• ⚠️ Minimal risk: could mask malformed schemas, but Pydantic auto-generates these, so unlikely

Tested:

• Failing case (Confluence API with Any field) now works
• Typed fields and signatures remain correct

Files:

• composio/utils/openapi.py