feat(snuba): Add conversation_id and session_id to TraceItem

[phacops]

Summary

Adds two new string fields to the TraceItem protobuf (proto/sentry_protos/snuba/v1/trace_item.proto):

• conversation_id (field 10) — the ID of the conversation this item belongs to, if any.
• session_id (field 11) — the ID of the session this item belongs to, if any.

These let trace items be associated with a conversation and a session.

Details

• Both fields are string, consistent with the existing trace_id field.
• They use the next available tag numbers (10, 11) in the public field range, so the change is purely additive and backwards compatible.
• Regenerated the Rust bindings (rust/src/sentry_protos.snuba.v1.rs). The Python bindings are gitignored, so they are not committed (they regenerate from the proto).
• Cargo.lock picked up an in-flight 0.32.4 → 0.32.5 version sync, matching the pattern of other recent feature PRs.
• CHANGELOG.md / VERSION are intentionally left untouched — those are bumped by the automated release process, not in feature PRs.

Testing

• make build-rust (regenerates bindings; compiles cleanly via cargo build).
• make build-py (Python bindings generate successfully).
• Verified a serialize/parse round-trip of the new fields in Python.
• pytest py/tests/test_snuba_v1.py — all 14 tests pass.

🤖 Generated with Claude Code

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Generated by Claude Code

[github-actions]

The latest Buf updates on your PR. Results from workflow ci / buf-checks (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Jun 23, 2026, 5:35 PM