The guild roster's zone and class keys went through `abstaining`, which answered `Equal` whenever either value was empty. So `"" = "Mage"` and `"" = "Warrior"` while `"Mage" < "Warrior"`: not a total order, and since Rust 1.81 `sort_unstable_by` may panic on one. The feed writes `""` for any class or zone id with no name. In the same comparator, the both-offline arm ordered `last_online_days`, a wire float, with `partial_cmp().unwrap_or(Equal)`, so a NaN equalled everything.
The reference's class arm (`0x4d0e25`-`0x4d0e2f`, `ChrClasses`) and zone arm (`0x4d0e9f`-`0x4d0ea5`, `AreaTable`) jump to `0x4d0efd` when either row is missing: a tie that passes to the next key. Now:
- `misses_last` compares two resolved names as before;
- two misses tie, so the next key decides, as in the reference;
- a miss orders after every name, marked as a deviation, since no total order can tie there;
- the offline arm uses `f32::total_cmp`.
`every_key_is_a_total_order_over_mixed_rows` checks antisymmetry and transitivity for Zone, Class and Online over 24 mixed rows, a NaN included. `sorting_a_mixed_roster_puts_misses_after_hits` checks the sorted order. Both fail with the old arms, as does `the_online_tiebreak_and_the_dbc_miss_order`. Built and gated on macOS.
Fixes#614🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
