Add middleware documentation

Author: DanielleHuisman

book/src/compute-position.md

@@ -220,7 +220,7 @@ cleanup();
 
 ## Options
 
-Passed as a third argument, this is the object to configure the behavior.
+Passed as a third argument, this is the struct instance to configure the behavior.
 
 ```rust,ignore
 compute_position(reference_el, floating_el, ComputePositionConfig::new());
@@ -356,7 +356,6 @@ fn wrapper(reference_el: Element, floating_el: Element, options: Options) -> Com
 `compute_position()` returns the following type:
 
 ```rust,ignore
-
 pub struct ComputePositionReturn {
     pub x: f64,
     pub y: f64,

book/src/frameworks/leptos.md

@@ -53,7 +53,7 @@ This will position the floating `Tooltip` element at the bottom center of the `B
 
 ### Disabling Transform
 
-By default, the floating element is positioned using `transform` in the `floating_styles` object. This is the most performant way to position elements, but can be disabled:
+By default, the floating element is positioned using `transform` in the `floating_styles` struct instance. This is the most performant way to position elements, but can be disabled:
 
 ```rust,ignore
 use_floating(reference_ref, floating_ref, UseFloatingOptions::default().transform(false.into()));