Major frontend code cleanup (#452)

Many large changes, including:
- TypeScript enums are now string unions throughout
- Strong type-checking throughout the TS and Vue codebase
- Vue component props now all specify `as PropType<...>`
- Usage of annotated return types on all functions
- Sorting of JS import statements
- Explicit usage of Vue bind attribute function call arguments (`@click="foo"` is now `@click=(e) => foo(e)`)
- Much improved code quality related to the color picker
- Consistent camelCase Vue bind and v-model attributes
- Consistent Vue HTML attribute strings with single quotes
- Bug fix and clarity improvement with incorrect hint class parameters
- Empty Vue component objects like `props: {}` and `components: {}` removed

frontend/src/dispatcher/js-dispatcher.ts

@@ -1,4 +1,5 @@
 import { plainToInstance } from "class-transformer";
+
 import { JsMessageType, messageConstructors, JsMessage } from "@/dispatcher/js-messages";
 import type { RustEditorInstance, WasmInstance } from "@/state/wasm-loader";
 
@@ -10,14 +11,15 @@ type JsMessageCallbackMap = {
 	[message: string]: JsMessageCallback<any> | undefined;
 };
 
+// eslint-disable-next-line @typescript-eslint/explicit-function-return-type
 export function createJsDispatcher() {
 	const subscriptions: JsMessageCallbackMap = {};
 
-	const subscribeJsMessage = <T extends JsMessage, Args extends unknown[]>(messageType: new (...args: Args) => T, callback: JsMessageCallback<T>) => {
+	const subscribeJsMessage = <T extends JsMessage, Args extends unknown[]>(messageType: new (...args: Args) => T, callback: JsMessageCallback<T>): void => {
 		subscriptions[messageType.name] = callback;
 	};
 
-	const handleJsMessage = (messageType: JsMessageType, messageData: Record<string, unknown>, wasm: WasmInstance, instance: RustEditorInstance) => {
+	const handleJsMessage = (messageType: JsMessageType, messageData: Record<string, unknown>, wasm: WasmInstance, instance: RustEditorInstance): void => {
 		const messageConstructor = messageConstructors[messageType];
 		if (!messageConstructor) {
 			// eslint-disable-next-line no-console

frontend/src/dispatcher/js-messages.ts

@@ -30,7 +30,7 @@ export abstract class DocumentDetails {
 
 	readonly id!: BigInt | string;
 
-	get displayName() {
+	get displayName(): string {
 		return `${this.name}${this.is_saved ? "" : "*"}`;
 	}
 }
@@ -44,25 +44,43 @@ export class UpdateOpenDocumentsList extends JsMessage {
 	readonly open_documents!: FrontendDocumentDetails[];
 }
 
-export type HintData = HintInfo[][];
-
 export class UpdateInputHints extends JsMessage {
 	@Type(() => HintInfo)
 	readonly hint_data!: HintData;
 }
 
-export type KeysGroup = string[];
+export type HintData = HintGroup[];
+
+export type HintGroup = HintInfo[];
 
 export class HintInfo {
-	readonly keys!: string[];
+	readonly key_groups!: KeysGroup[];
 
-	readonly mouse!: KeysGroup | null;
+	readonly mouse!: MouseMotion | null;
 
 	readonly label!: string;
 
 	readonly plus!: boolean;
 }
 
+export type KeysGroup = string[]; // Array of Rust enum `Key`
+
+export type MouseMotion = string;
+
+export type RGBA = {
+	r: number;
+	g: number;
+	b: number;
+	a: number;
+};
+
+export type HSVA = {
+	h: number;
+	s: number;
+	v: number;
+	a: number;
+};
+
 const To255Scale = Transform(({ value }) => value * 255);
 export class Color {
 	@To255Scale
@@ -76,11 +94,11 @@ export class Color {
 
 	readonly alpha!: number;
 
-	toRgba() {
+	toRgba(): RGBA {
 		return { r: this.red, g: this.green, b: this.blue, a: this.alpha };
 	}
 
-	toRgbaCSS() {
+	toRgbaCSS(): string {
 		const { r, g, b, a } = this.toRgba();
 		return `rgba(${r}, ${g}, ${b}, ${a})`;
 	}
@@ -296,17 +314,7 @@ export class LayerMetadata {
 	selected!: boolean;
 }
 
-export const LayerTypeOptions = {
-	Folder: "Folder",
-	Shape: "Shape",
-	Circle: "Circle",
-	Rect: "Rect",
-	Line: "Line",
-	PolyLine: "PolyLine",
-	Ellipse: "Ellipse",
-} as const;
-
-export type LayerType = typeof LayerTypeOptions[keyof typeof LayerTypeOptions];
+export type LayerType = "Folder" | "Shape" | "Circle" | "Rect" | "Line" | "PolyLine" | "Ellipse";
 
 export class IndexedDbDocumentDetails extends DocumentDetails {
 	@Transform(({ value }: { value: BigInt }) => value.toString())