search panics on short intervals

[yorik]

Describe the bug

The same query like pod_name:"foo-0" AND custom_field:12345 success on 12h interval but fails on intervals 3h or shorter.
Log:

2026-02-18T14:37:20.483Z  INFO leaf_search:multi_index_leaf_search{index=["testnet"]}: quickwit_search::leaf: num_docs=1025393 num_splits=1 split_offsets=[SplitIdAndFooterOffsets { split_id: "XXXXXXXXXXXXXXXXXXXXXXXXXX", split_footer_start: 85152833, split_footer_end: 85182232, timestamp_start: Some(1771396563), timestamp_end: Some(1771422517), num_docs: 1025393 }]

thread 'quickwit-search-0' (15) panicked at /usr/local/cargo/git/checkouts/tantivy-9cf9af06161d52ce/d904630/src/positions/reader.rs:142:18:
copy_from_slice: source slice length (0) does not match destination slice length (67)

thread 'quickwit-search-0' (16) panicked at /usr/local/cargo/git/checkouts/tantivy-9cf9af06161d52ce/d904630/src/positions/reader.rs:142:18:
copy_from_slice: source slice length (0) does not match destination slice length (65)
2026-02-18T14:37:25.106Z ERROR quickwit_common::thread_pool: task running in the quickwit search thread pool panicked

Steps to reproduce (if applicable)
Steps to reproduce the behavior:

1. Query in grafana pod_name:"foo-0" AND custom_field:12345
2. Select time interval to be a shorter than 3h

Expected behavior
It's expected to see the logs from the interval with custom_field:12345

Configuration:
Please provide:

1. Output of quickwit --version

Quickwit 0.8.0 (x86_64-unknown-linux-gnu 2026-01-14T22:07:01Z d8fc982)

2. The index_config.yaml
   We don't have index_config.yaml