feat: Engine diagnostics (#92)

Adds a `Diagnostics` component that shows the following diagnostics from the last realization:

- Confirmation of success or a short description of what failed.
- The value of the loss function at each step.
- The spectrum of the Hessian at each step.

The loss and spectrum plots are shown on switchable panels.

Also includes some refactoring/renaming of existing code.

Co-authored-by: Aaron Fenyes <aaron.fenyes@fareycircles.ooo>
Reviewed-on: #92
Co-authored-by: Vectornaut <vectornaut@nobody@nowhere.net>
Co-committed-by: Vectornaut <vectornaut@nobody@nowhere.net>

app-proto/src/main.rs

@@ -1,5 +1,6 @@
 mod add_remove;
 mod assembly;
+mod diagnostics;
 mod display;
 mod engine;
 mod outline;
@@ -13,6 +14,7 @@ use sycamore::prelude::*;
 
 use add_remove::AddRemove;
 use assembly::{Assembly, Element};
+use diagnostics::Diagnostics;
 use display::Display;
 use outline::Outline;
 
@@ -60,6 +62,7 @@ fn main() {
             div(id="sidebar") {
                 AddRemove {}
                 Outline {}
+                Diagnostics {}
             }
             Display {}
         }