fix(stats): last_usage orders by id (insertion order); clarify Window default

hive-ag3nt/src/stats.rs

@@ -42,6 +42,7 @@ impl Window {
             "7d" => Self::Week,
             "30d" => Self::Month,
             "all" => Self::All,
+            // Default (incl. `label()`'s own canonical `"24h"`/`"1d"`).
             _ => Self::Day,
         }
     }

hive-ag3nt/src/turn_stats.rs

@@ -289,7 +289,10 @@ impl TurnStats {
                     last_input_tokens, last_output_tokens,
                     last_cache_read_input_tokens, last_cache_creation_input_tokens
              FROM turn_stats
-             ORDER BY started_at DESC
+             -- `id` (AUTOINCREMENT) is monotonic with insertion, so this is
+             -- the most-recently-inserted row even among same-second turns
+             -- (which `started_at DESC` would order arbitrarily).
+             ORDER BY id DESC
              LIMIT 1",
             [],
             |row| {