more strict props

let people type it loose themselves if they want to

src/runtime/internal/Component.ts

@@ -217,7 +217,7 @@ export class SvelteComponent<
 	Events extends Record<string, any> = any
 > {
 	$$: T$$;
-	$$set?: ($$props: Partial<Props> & Record<string, any>) => void;
+	$$set?: ($$props: Partial<Props>) => void;
 
 	$destroy() {
 		destroy_component(this, 1);
@@ -234,7 +234,7 @@ export class SvelteComponent<
 		};
 	}
 
-	$set($$props: Partial<Props> & Record<string, any>) {
+	$set($$props: Partial<Props>) {
 		if (this.$$set && !is_empty($$props)) {
 			this.$$.skip_bound = true;
 			this.$$set($$props);

src/runtime/internal/dev.ts

@@ -102,7 +102,7 @@ export interface SvelteComponentDev<
 	Events extends Record<string, any> = any,
 	Slots extends Record<string, any> = any
 > {
-	$set(props?: Partial<Props> & Record<string, any>): void;
+	$set(props?: Partial<Props>): void;
 	$on<K extends Extract<keyof Events, string>>(type: K, callback: (e: Events[K]) => void): () => void;
 	$destroy(): void;
 	[accessor: string]: any;
@@ -138,7 +138,7 @@ export class SvelteComponentDev<
 	constructor(options: {
 		target: Element;
 		anchor?: Element;
-		props?: Props & Record<string, any>;
+		props?: Props;
 		hydrate?: boolean;
 		intro?: boolean;
 		$$inline?: boolean;