Function snapshot_checked 

pub fn snapshot_checked(
    ids: &[u32],
    max_entries: usize,
    max_utf8_bytes: usize,
) -> Result<SymbolSnapshot, SymbolSnapshotError>

Copies all requested symbols under one read lock, or returns no snapshot.

Count and UTF-8 byte bounds include duplicates. All IDs and byte lengths are checked before copying any text; no registry entry is added or renumbered.