fix(engine,server): safe area clamp, analytics batch, achievement save order, daily rollover, replay validation, leaderboard opt-in (#56, #60, #61, #62, #66, #68)

- #66: Clamp safe-area insets to 25% of window height with warn!() on excess
- #68: Move fire_flush outside per-event loop in analytics (batch flush once)
- #56: Persist progress before marking reward_granted to prevent XP loss on crash
- #60: Add DateRolloverTimer + check_date_rollover system for midnight seed refresh
- #62: Add validate_header() in replay upload with mode/draw_mode allowlists
- #61: Restore two-query leaderboard opt-in check (SELECT then UPDATE); original
       queries already in .sqlx cache; EXISTS variant would require sqlx prepare

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

solitaire_engine/src/challenge_plugin.rs

@@ -58,12 +58,15 @@ fn advance_on_challenge_win(
         let prev = progress.0.challenge_index;
         progress.0.challenge_index = prev.saturating_add(1);
         if let Some(target) = &path.0
-            && let Err(e) = save_progress_to(target, &progress.0) {
-                warn!("failed to save progress after challenge advance: {e}");
-            }
+            && let Err(e) = save_progress_to(target, &progress.0)
+        {
+            warn!("failed to save progress after challenge advance: {e}");
+        }
         // Human-readable level is 1-based (index 0 → "Challenge 1").
         let level_number = prev.saturating_add(1);
-        toast.write(InfoToastEvent(format!("Challenge {level_number} complete!")));
+        toast.write(InfoToastEvent(format!(
+            "Challenge {level_number} complete!"
+        )));
         advanced.write(ChallengeAdvancedEvent {
             previous_index: prev,
             new_index: progress.0.challenge_index,
@@ -184,8 +187,7 @@ mod tests {
     #[test]
     fn pressing_x_at_unlock_level_fires_new_game_with_challenge_seed() {
         let mut app = headless_app();
-        app.world_mut().resource_mut::<ProgressResource>().0.level =
-            CHALLENGE_UNLOCK_LEVEL;
+        app.world_mut().resource_mut::<ProgressResource>().0.level = CHALLENGE_UNLOCK_LEVEL;
         app.world_mut()
             .resource_mut::<ProgressResource>()
             .0
@@ -215,7 +217,10 @@ mod tests {
     fn challenge_win_fires_complete_toast_with_level_number() {
         let mut app = headless_app();
         // Set challenge_index to 2 so the completed level is "Challenge 3".
-        app.world_mut().resource_mut::<ProgressResource>().0.challenge_index = 2;
+        app.world_mut()
+            .resource_mut::<ProgressResource>()
+            .0
+            .challenge_index = 2;
         app.world_mut().resource_mut::<GameStateResource>().0 =
             GameState::new_with_mode(1, DrawMode::DrawOne, GameMode::Challenge);
 
@@ -228,7 +233,11 @@ mod tests {
         let events = app.world().resource::<Messages<InfoToastEvent>>();
         let mut cursor = events.get_cursor();
         let fired: Vec<_> = cursor.read(events).collect();
-        assert_eq!(fired.len(), 1, "exactly one toast must fire on challenge win");
+        assert_eq!(
+            fired.len(),
+            1,
+            "exactly one toast must fire on challenge win"
+        );
         assert!(
             fired[0].0.contains("Challenge 3"),
             "toast must name the 1-based level that was just completed"