feat(weave): write explicit 'latest' alias on every obj_create (WB-32435)

[rgao-coreweave]

Summary

• Writes an explicit "latest" alias to the aliases table on every obj_create, so re-publishing old content promotes it to "latest" — matching W&B Artifacts behavior
• Updates _maybe_resolve_alias to resolve "latest" from the aliases table first, falling back to computed is_latest for legacy objects
• Updates the query builder so alias-based filtering for "latest" checks both the explicit alias and the computed is_latest

Changes

• ClickHouse obj_create: calls _insert_aliases("latest") after every insert
• _maybe_resolve_alias: resolves "latest" from aliases table with _resolve_computed_latest fallback
• _enrich_objs_with_tags_and_aliases: only synthesizes "latest" from is_latest for objects without an explicit alias row
• Query builder add_aliases_condition: includes "latest" in alias subquery alongside is_latest = 1 OR fallback
• SQLite obj_create: writes "latest" alias in both dedup and new-insert paths

Test plan

• test_obj_create_writes_latest_alias — verifies alias is written
• test_obj_create_moves_latest_alias_on_new_version — alias moves on new version
• test_obj_create_moves_latest_alias_on_dedup — alias moves on re-publish (dedup)
• test_resolve_latest_falls_back_to_computed — legacy objects without alias still work
• test_resolve_computed_latest_returns_none_for_missing — nonexistent object returns None
• Updated query builder SQL expectations
• Updated alias list tests to expect "latest"
• Full trace_server shard (CH): 776 passed
• Full alias tests (SQLite): 145 passed
• Ruff check + format: clean

[rgao-coreweave]

• feat(weave): write explicit 'latest' alias on every obj_create (WB-32435) #6481 👈 (View in Graphite)
• master

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[wandbot-3000]

Preview this PR with FeatureBee: https://beta.wandb.ai/?betaVersion=f788d7eadc800ae0308cc294718ab8dee7a1ffc7

[codecov]

Codecov Report

❌ Patch coverage is 93.93939% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...ve/trace_server/clickhouse_trace_server_batched.py	94.11%	0 Missing and 1 partial ⚠️
weave/trace_server/sqlite_trace_server.py	91.66%	0 Missing and 1 partial ⚠️

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[rgao-coreweave]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

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[rgao-coreweave]

Code review

Found 1 issue:

1. SQLite _maybe_resolve_alias was not updated to resolve "latest" from the aliases table. It still has if digest == "latest": return None (line 4760), which bypasses the alias table entirely. The ClickHouse version was updated to resolve "latest" from aliases with a computed fallback, but the SQLite path was missed. This means the core PR semantic (re-publishing old content promotes to latest) does not work for SQLite obj_read("latest"). The dedup test (test_obj_create_moves_latest_alias_on_dedup) only runs against ClickHouse via ch_server.

weave/weave/trace_server/sqlite_trace_server.py

Lines 4759 to 4762 in 054b8ed

	# content hashes are real digests that don't need resolution.
	if digest == "latest":
	return None
	(is_version, _) = digest_is_version_like(digest)

[github-actions]

This PR has been inactive for 14 days. It will be closed in 7 days unless there is new activity.

[github-actions]

Closing this PR due to inactivity.