Update SDK for Codex 0.65, add strong typing and Nix devshell support

Expand property tests and parsing to cover literals and multi-branch unions

Merge pull request #1 from darinkishore/claude/refactor-dspy-output-01Bz24ZA6ZHAsbMS66mhkRU9

Fix optional list outputs skipping model validation

Hoist $defs to root in output_schema for nested Pydantic models

Mark optional output fields with ? in TypeScript Response type

Document TypeScript Turn 2 format and static examples in README

Add TypeScript code fences to Turn 2 prompt formatting

Add TypeScript-based Turn 2 formatting for structured output

Fix list[Model | None] rendering in turn2 prompts

Refactor output parsing with TDD tests

Add edge case tests for complex type annotations

Fix double-bracketed list type in turn2 prompt

Fix PEP 604 optional fields in JSON schema required list

Fix list[PydanticModel] output validation