feat(snuba): Add AI_CONVERSATION trace item type

[pbhandari]

Summary

Adds TRACE_ITEM_TYPE_AI_CONVERSATION to the TraceItemType enum in snuba/v1.

AI conversations can be queried through the existing TraceItemTable endpoint by setting RequestMeta.trace_item_type to this new value. TraceItemTable already supports everything the use case needs:

• Arbitrary field selection via columns (each Column may be a plain attribute)
• Aggregation (sum, count, …) via Column.aggregation
• Conditional aggregation (sumIf / countIf) via Column.conditional_aggregation
• Filtering via filter, ordering via order_by, and HAVING via aggregation_filter

So no new endpoint is required — a dedicated GetAiConversations request/response would have been a strict subset of TraceItemTableRequest. Adding an enum value is backwards compatible.

Test plan

• buf lint / buf format pass (pre-commit)
• protoc compiles the package cleanly

🤖 Generated with 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	Jul 20, 2026, 3:33 PM

[sentry]

Bug: The auto-generated Rust code in rust/src/sentry_protos.snuba.v1.rs is out of sync with the updated protobuf definition, missing the new TRACE_ITEM_TYPE_AI_CONVERSATION enum variant.
_{Severity: CRITICAL}

Suggested Fix

Run the code generation script to update the auto-generated Rust files. Based on the CI configuration, this can be done by running make build-rust locally. Commit the updated rust/src/sentry_protos.snuba.v1.rs file to ensure the Rust code is synchronized with the protobuf definition before merging.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: proto/sentry_protos/snuba/v1/request_common.proto#L80

Potential issue: The protobuf definition in `request_common.proto` was updated to
include `TRACE_ITEM_TYPE_AI_CONVERSATION`, but the corresponding auto-generated Rust
code in `rust/src/sentry_protos.snuba.v1.rs` was not regenerated. As a result, the Rust
`TraceItemType` enum is missing the `AiConversation` variant. This will cause
deserialization failures when any Rust service attempts to process a protobuf message
containing `trace_item_type = 14`. The value may be incorrectly interpreted as
`Unspecified` or cause a runtime error, preventing the new feature from working in
Rust-based consumers.

_{Did we get this right? 👍 / 👎 to inform future reviews.}