Vue initialization and FloatingMenu codebase refactoring and cleanup (#649)

* Clean up Vue initialization-related code

* Rename folder: dispatcher -> interop

* Rename folder: state -> providers

* Comments and clarification

* Rename JS dispatcher to subscription router

* Assorted cleanup and renaming

* Rename: js-messages.ts -> messages.ts

* Comments

* Remove unused Vue component injects

* Clean up coming soon and add warning about freezing the app

* Further cleanup

* Dangerous changes

* Simplify App.vue code

* Move more disparate init code from components into managers

* Rename folder: providers -> state-providers

* Other

* Move Document panel options bar separator to backend

* Add destructors to managers to fix HMR

* Comments and code style

* Rename variable: font -> font_file_url

* Fix async font loading; refactor janky floating menu openness and min-width measurement; fix Vetur errors

* Fix misaligned canvas in viewport until panning on page (re)load

* Add Vue bidirectional props documentation

* More folder renaming for better terminology; add some documentation

frontend/src/utility-functions/panic-proxy.ts

@@ -0,0 +1,40 @@
+// This works by proxying every function call and wrapping a try-catch block to filter out redundant and confusing
+// `RuntimeError: unreachable` exceptions that would normally be printed in the browser's JS console upon a panic.
+export function panicProxy<T extends object>(module: T): T {
+	const proxyHandler = {
+		get(target: T, propKey: string | symbol, receiver: unknown): unknown {
+			const targetValue = Reflect.get(target, propKey, receiver);
+
+			// Keep the original value being accessed if it isn't a function
+			const isFunction = typeof targetValue === "function";
+			if (!isFunction) return targetValue;
+
+			// Special handling to wrap the return of a constructor in the proxy
+			const isClass = isFunction && /^\s*class\s+/.test(targetValue.toString());
+			if (isClass) {
+				// eslint-disable-next-line func-names
+				return function (...args: unknown[]): unknown {
+					// eslint-disable-next-line new-cap
+					const result = new targetValue(...args);
+					return panicProxy(result);
+				};
+			}
+
+			// Replace the original function with a wrapper function that runs the original in a try-catch block
+			// eslint-disable-next-line func-names
+			return function (...args: unknown[]): unknown {
+				let result;
+				try {
+					// @ts-expect-error TypeScript does not know what `this` is, since it should be able to be anything
+					result = targetValue.apply(this, args);
+				} catch (err) {
+					// Suppress `unreachable` WebAssembly.RuntimeError exceptions
+					if (!`${err}`.startsWith("RuntimeError: unreachable")) throw err;
+				}
+				return result;
+			};
+		},
+	};
+
+	return new Proxy<T>(module, proxyHandler);
+}