fix: make grocery and reference ordering deterministic

Every list query lacked a tiebreak, so rows sharing a sort key (same-ms
createdAt inserts, tied or NULL quality scores) came back in unspecified
order and bestRef flipped between loads. Add explicit tiebreaks: items
createdAt desc, id desc (newest first); references qualityScore desc,
id asc (first inserted wins ties). Categories were already total
(order, name unique).

Pin the rules with service tests.

1 files changed, 0 insertions, 1 deletions

diff --git a/README.md b/README.md
index 76742d2..cd4ed0f 100644
--- a/README.md
+++ b/README.md
@@ -81,5 +81,4 @@ mise run deploy
 - Auto-categorize new items (LLM-assisted)
 - https://automerge.org/docs/tutorial/
 - Shared > Modal actions
-- Deterministic sort
 - Input + buttons sizes (ajouter un article)