Fix mount use after removal/Simplify mounts a bit (#2834)

* remove clone mounted; mounted nodes should never leak into components?

* Remove the mount from vnodes after unmounting them

* Fix use after removal in iterator diffing

* remove logs

* Re-fix keyed list diffing

* Use new.len for diffing keyed lens and remove redundant check

* simplify core list diffing logic a bit

* remove println

* add proper asserts for new tests

---------

Co-authored-by: Jonathan Kelley <jkelleyrtp@gmail.com>

packages/core/src/error_boundary.rs

@@ -451,17 +451,6 @@ impl CapturedError {
         self
     }
 
-    /// Clone the error while retaining the mounted information of the error
-    pub(crate) fn clone_mounted(&self) -> Self {
-        Self {
-            error: self.error.clone(),
-            backtrace: self.backtrace.clone(),
-            scope: self.scope,
-            render: self.render.clone_mounted(),
-            context: self.context.clone(),
-        }
-    }
-
     /// Get a VNode representation of the error if the error provides one
     pub fn show(&self) -> Option<Element> {
         if self.render == VNode::placeholder() {