Use signed i64 generated tie breakers + bump Tantivy

[Mallets]

Summary

• Pin tantivy and tantivy-common to latest Tantivy main at 2e87c2eb0c8577c96c82a777f345bbf236a985fe, which includes the merged Generate tie-breakers as i64 values tantivy#3158. Lockfile changes are limited to the Tantivy git revision.
• Treat tie_breaker fields as i64 when parsing term/range queries and converting values to JSON.
• Update the field documentation and validate signed sort values, the generated i32 range, term/range queries, and one-event search_after pagination in both directions.

Motivation

Downstream cursors represent tie-breakers as signed integers. Tantivy #3158 maps generated values onto the signed i32 range while retaining 32 bits of entropy, allowing generated and legacy explicit i64 tie-breakers to share the same representation.

Backward compatibility

#6859 has been merged few days ago, I don't expect tiebreakers are used by any existing deployments .

Validation

• cargo check -p quickwit-doc-mapper -p quickwit-query -p quickwit-search: passed.
• cargo test -p quickwit-query: 184 passed.
• cargo test -p quickwit-search --lib: 226 passed.
• cargo test -p quickwit-query -p quickwit-doc-mapper -p quickwit-search tie_breaker: 9 passed.
• cargo test -p quickwit-doc-mapper: 232 passed; test_concatenate_multiple_field fails due to concatenated string ordering. Reproduced the identical failure in a clean worktree at origin/main (8952853b8) using the original Tantivy dependency. No unrelated test changes made.
• cargo clippy -p quickwit-doc-mapper -p quickwit-query -p quickwit-search --all-targets -- -D warnings: passed.
• make fmt (formatting, license headers, log format) and git diff --check: passed.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-07T09:58:01.253166Z	4d9767e	Draft marked ready

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