chore(workspace): fix all clippy warnings in test code

Resolves 15 violations found by `cargo clippy --workspace --tests -D warnings`:
- Remove unused imports (Card, Rank) in cursor_plugin tests
- Replace absurd i32::MAX comparison with a meaningful >= 0 check
- Use range .contains() instead of manual >= && <= (manual_range_contains)
- Move impl FromRequestParts before test module in middleware.rs (items_after_test_module)
- Move _VEC3_REFERENCED const before test module in input_plugin.rs
- Convert runtime assert on constant to const { assert!(...) }
- Use .contains() instead of .iter().any() for slice membership
- Replace .get(...).is_none() with !.contains_key(...) in HashMap checks
- Collapse Default::default() + field assignment into struct literal initializers
  across solitaire_sync, solitaire_data, and solitaire_engine test helpers

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

solitaire_server/src/middleware.rs

@@ -100,6 +100,22 @@ pub fn validate_refresh_token(token: &str, secret: &str) -> Result<Claims, AppEr
 // Axum extractor — allows handlers to receive AuthenticatedUser directly
 // ---------------------------------------------------------------------------
 
+#[axum::async_trait]
+impl<S> FromRequestParts<S> for AuthenticatedUser
+where
+    S: Send + Sync,
+{
+    type Rejection = AppError;
+
+    async fn from_request_parts(parts: &mut Parts, _state: &S) -> Result<Self, Self::Rejection> {
+        parts
+            .extensions
+            .get::<AuthenticatedUser>()
+            .cloned()
+            .ok_or(AppError::Unauthorized)
+    }
+}
+
 // ---------------------------------------------------------------------------
 // Tests
 // ---------------------------------------------------------------------------
@@ -221,19 +237,3 @@ mod tests {
         assert!(result.is_err(), "expired refresh token must be rejected");
     }
 }
-
-#[axum::async_trait]
-impl<S> FromRequestParts<S> for AuthenticatedUser
-where
-    S: Send + Sync,
-{
-    type Rejection = AppError;
-
-    async fn from_request_parts(parts: &mut Parts, _state: &S) -> Result<Self, Self::Rejection> {
-        parts
-            .extensions
-            .get::<AuthenticatedUser>()
-            .cloned()
-            .ok_or(AppError::Unauthorized)
-    }
-}