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/card_animation/tuning.rs

@@ -114,7 +114,7 @@ impl AnimationTuning {
             platform: InputPlatform::Touch,
             duration_scale: 0.75,
             overshoot_scale: 0.5,
-            drag_threshold_px: 8.0,  // Android ViewConfiguration.getScaledTouchSlop()
+            drag_threshold_px: 8.0, // Android ViewConfiguration.getScaledTouchSlop()
             drag_scale: 1.12,
             hover_scale: 1.0, // no hover affordance on touch
             hover_lerp_speed: 20.0,
@@ -182,15 +182,24 @@ mod tests {
         assert_eq!(t.duration_scale, 1.0);
         assert_eq!(t.platform, InputPlatform::Mouse);
         assert!(t.hover_scale > 1.0, "desktop hover must lift the card");
-        assert!(t.drag_threshold_px < 10.0, "desktop threshold must be smaller than mobile");
+        assert!(
+            t.drag_threshold_px < 10.0,
+            "desktop threshold must be smaller than mobile"
+        );
     }
 
     #[test]
     fn mobile_is_faster_than_desktop() {
         let d = AnimationTuning::desktop();
         let m = AnimationTuning::mobile();
-        assert!(m.duration_scale < d.duration_scale, "mobile must animate faster");
-        assert!(m.overshoot_scale < d.overshoot_scale, "mobile must bounce less");
+        assert!(
+            m.duration_scale < d.duration_scale,
+            "mobile must animate faster"
+        );
+        assert!(
+            m.overshoot_scale < d.overshoot_scale,
+            "mobile must bounce less"
+        );
     }
 
     #[test]