fix(google_genai): serialize Content objects with nested binary Parts as attachments

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167

[Abhijeet Prasad (AbhiPrasad)]

Content objects wrapping binary Parts (e.g.
types.Content(parts=[Part.from_bytes(...), ...])) were returned un-serialized by _serialize_content_item, leaking raw bytes into logged spans instead of converting inline_data to Attachment objects.

Refactored the serialization pass to only do what bt_safe_deep_copy cannot: walk the Content/Part tree and replace binary inline_data with Attachments. All other serialization (text parts, Pydantic model_dump, etc.) is left to bt_safe_deep_copy downstream, removing the redundant model_dump/dump/to_dict fallback chain.

Adds a unit test for _serialize_content_item with a Content wrapper and a VCR-backed integration test for generate_content with Content-wrapped binary+text parts.

supercedes #167