chore: cargo fmt across workspace; add analytics domain to CSP

- Apply cargo fmt to solitaire_engine, solitaire_server formatting.
- solitaire_server/src/lib.rs: add https://analytics.aleshym.co to
  script-src, img-src, and connect-src so the analytics beacon loads
  without a CSP violation.
- docs and README updates.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

solitaire_engine/src/resources.rs

@@ -6,8 +6,8 @@ use std::sync::Arc;
 use bevy::math::Vec2;
 use bevy::prelude::Resource;
 use chrono::{DateTime, Utc};
-use solitaire_core::game_state::GameState;
 use klondike::KlondikePile;
+use solitaire_core::game_state::GameState;
 
 /// Wraps the currently active `GameState`. Single source of truth for the in-progress game.
 #[derive(Resource, Debug, Clone)]