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/animation.rs

@@ -34,7 +34,7 @@ use std::f32::consts::PI;
 
 use bevy::prelude::*;
 
-use super::curves::{sample_curve, MotionCurve};
+use super::curves::{MotionCurve, sample_curve};
 use super::timing::compute_duration;
 use crate::pause_plugin::PausedResource;
 
@@ -192,7 +192,11 @@ pub fn retarget_animation(
             let carry = (t * 0.12).min(0.10);
             (anim.current_xy(), transform.translation.z, carry)
         }
-        _ => (transform.translation.truncate(), transform.translation.z, 0.0),
+        _ => (
+            transform.translation.truncate(),
+            transform.translation.z,
+            0.0,
+        ),
     };
 
     let distance = current_xy.distance(new_end);
@@ -328,7 +332,10 @@ mod tests {
     fn current_xy_at_start() {
         let anim = make_anim(Vec2::ZERO, Vec2::new(100.0, 0.0), 0.0, 1.0);
         let pos = anim.current_xy();
-        assert!(pos.x < 5.0, "at t=0 position should be near start, got {pos:?}");
+        assert!(
+            pos.x < 5.0,
+            "at t=0 position should be near start, got {pos:?}"
+        );
     }
 
     #[test]
@@ -390,7 +397,10 @@ mod tests {
     fn win_scatter_targets_are_off_center() {
         for t in win_scatter_targets(400.0) {
             let dist = t.length();
-            assert!(dist > 100.0, "scatter target should be well off-center: {t:?}");
+            assert!(
+                dist > 100.0,
+                "scatter target should be well off-center: {t:?}"
+            );
         }
     }
 }