style: cargo fmt under rustfmt 1.9 and gate formatting in CI

The repo was formatted under an older stable; rustfmt 1.9 (Rust 1.95)
wraps signatures and call sites differently, so every touched file was
picking up unrelated formatting hunks. One mechanical pass, and a
'cargo fmt --check' step in the test workflow (same pinned 1.95.0
toolchain) so drift can't accumulate again.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

solitaire_engine/src/card_plugin/layout.rs

@@ -15,10 +15,7 @@ use crate::font_plugin::FontResource;
 use crate::layout::{Layout, LayoutResource};
 use crate::resources::GameStateResource;
 use crate::table_plugin::PileMarker;
-use crate::ui_theme::{
-    CARD_SHADOW_ALPHA_DRAG, CARD_SHADOW_PADDING_DRAG,
-    CARD_SHADOW_PADDING_IDLE,
-};
+use crate::ui_theme::{CARD_SHADOW_ALPHA_DRAG, CARD_SHADOW_PADDING_DRAG, CARD_SHADOW_PADDING_IDLE};
 
 /// Coalesces every `WindowResized` event arriving this frame into the latest
 /// pending size on [`ResizeThrottle`].
@@ -347,5 +344,3 @@ pub(super) fn fill_tableau_fan_on_startup(
     };
     crate::layout::apply_dynamic_tableau_fan(&game.0, &mut layout.0);
 }
-
-