chore(deps): update dependency pydantic-ai to >=1.39.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
pydantic-ai (changelog)	>=1.38.0 → >=1.39.0

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Release Notes

pydantic/pydantic-ai (pydantic-ai)

v1.39.0: (2025-12-23)

Compare Source

What's Changed

• Support embedding models by @​DouweM and @​dmontagu in #​3252
• Add Agent and agent run metadata and expose it on result objects and span attributes by @​sstanovnik in #​3370
• Support system prompts functions returning None by @​mrdkucher in #​3834
• Handle ThinkingPart in MCP Sampling by @​eekstunt in #​3823
• Add bedrock_service_tier setting to BedrockModelSettings by @​lukekh in #​3773
• Add docs and tests for RunContext.partial_output in output tools by @​Danipulok in #​3726
• Update docs about choosing priority of output and deferred tool calls with run_stream by @​Danipulok in #​3725
• docs: Fix cross references by @​sanxiyn in #​3809
• Add pydantic-deep + toolsets to docs by @​DouweM in #​3837

New Contributors

• @​sanxiyn made their first contribution in #​3809
• @​eekstunt made their first contribution in #​3823
• @​sstanovnik made their first contribution in #​3370
• @​mrdkucher made their first contribution in #​3834

Full Changelog: pydantic/pydantic-ai@v1.38.0...v1.39.0

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[claude]

PR Review

This dependency update looks good to merge with one minor consideration:

Changes

• Updates pydantic-ai from >=1.38.0 to >=1.39.0 in the examples dependency group
• Adds tiktoken as a new transitive dependency for OpenAI support

Analysis

✅ Scope: Limited to optional examples dependency group - no impact on core functionality
✅ Breaking Changes: None - this is a minor version bump (1.38.0 → 1.39.0)
✅ Code Impact: Only affects examples/anthropic_comparison/mcp_optimizer_agent.py
✅ New Features: The update adds embedding model support and agent metadata which could be useful for future examples

Notable Changes in 1.39.0

• Support for embedding models
• Agent and run metadata on result objects
• Handle ThinkingPart in MCP sampling (directly relevant to this project)
• tiktoken now explicitly included for OpenAI tokenization

Recommendation

LGTM - Safe to merge. The new tiktoken dependency is expected for OpenAI model usage and the MCP sampling improvements align with this project's goals.

No action required beyond standard merge.