Prettier 2: Electric Boogaloo (#6113)

# Description of Changes
When I added Prettier formatting in #6052, my aim was to use just the
default settings in Prettier. Turns out, Prettier looks _really hard_
for any config files if it's not explicitly given one, which means that
if a developer has some sort of Prettier config file lying around on
their system, Prettier might find it and use it. Also, Prettier changes
its defaults based on stuff in `.editorconfig` without any good way of
disabling that behaviour explicitly in its config file.

To solve both of these issues, I've introduced a `.prettierrc` file
which sets Prettier's defaults explicitly, and then reformatted all our
code _again_ in Prettier's actual default settings. This should achieve
the aim of #6052 and remove the possibility for it breaking on different
dev computers.

frontend/src/core/components/hotkeys/HotkeyDisplay.tsx

@@ -23,7 +23,11 @@ const baseKeyStyle: React.CSSProperties = {
   color: "var(--mantine-color-text)",
 };
 
-export const HotkeyDisplay: React.FC<HotkeyDisplayProps> = ({ binding, size = "sm", muted = false }) => {
+export const HotkeyDisplay: React.FC<HotkeyDisplayProps> = ({
+  binding,
+  size = "sm",
+  muted = false,
+}) => {
   const { getDisplayParts } = useHotkeys();
   const parts = getDisplayParts(binding);
 
@@ -31,7 +35,10 @@ export const HotkeyDisplay: React.FC<HotkeyDisplayProps> = ({ binding, size = "s
     return null;
   }
 
-  const keyStyle = size === "md" ? { ...baseKeyStyle, fontSize: "0.85rem", padding: "0.2rem 0.5rem" } : baseKeyStyle;
+  const keyStyle =
+    size === "md"
+      ? { ...baseKeyStyle, fontSize: "0.85rem", padding: "0.2rem 0.5rem" }
+      : baseKeyStyle;
 
   return (
     <span