fix: web client styling and nav updates (#21)

## Summary

- Aligns the client with the NHCarrigan style guide (witch palette, Griffy/Kalam fonts, shared stylesheet)
- Fixes sanctions page to sort by case number descending
- Updates all Hikari image URLs to `cdn.nhcarrigan.com/hikari.png`
- Adds Support link to nav (https://support.nhcarrigan.com)
- Fixes Chat nav link to point to https://chat.nhcarrigan.com

✨ This issue was created with help from Hikari~ 🌸

Reviewed-on: #21
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

client/src/app/nav/nav.css

@@ -6,11 +6,13 @@ nav {
   height: 40px;
   color: var(--foreground);
   background-color: var(--background);
+  border-bottom: 1px solid var(--border);
   display: flex;
   align-items: center;
   justify-content: space-between;
   padding-left: 15px;
   padding-right: 15px;
+  z-index: 100;
 }
 
 nav a:not(#logo) {
@@ -34,7 +36,7 @@ img {
 hr {
   width: 100%;
   border: none;
-  border-top: 1px solid var(--foreground);
+  border-top: 1px solid var(--border);
   margin: 0;
 }
 
@@ -50,7 +52,7 @@ hr {
   top: 40px;
   background-color: var(--background);
   color: var(--foreground);
-  border: 1px solid var(--foreground);
+  border: 1px solid var(--border);
   border-radius: 5px;
   box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
 }
@@ -59,7 +61,6 @@ hr {
   display: flex;
   align-items: center;
   justify-content: center;
-  cursor: url('https://cdn.nhcarrigan.com/cursors/pointer.cur'), pointer;
   text-decoration: none;
   font-size: 2rem;
 }