chore: clear the mechanical lint and type findings

Dead imports and locals removed, each blocks keyed, `any` narrowed to unknown.
Two context setters kept their calls and lost only the unused binding; the
settings redirect no longer awaits a parent whose data it discards. A leading
underscore now marks a binding that only holds a position.

frontend/src/lib/server/api.ts

@@ -21,7 +21,7 @@ export class ApiClient {
 		return this.request(endpoint);
 	}
 
-	async post(endpoint: string, data: any): Promise<Response> {
+	async post(endpoint: string, data: unknown): Promise<Response> {
 		return this.request(endpoint, {
 			method: 'POST',
 			headers: {
@@ -48,7 +48,7 @@ export class ApiClient {
 		});
 	}
 
-	async put(endpoint: string, data: any): Promise<Response> {
+	async put(endpoint: string, data: unknown): Promise<Response> {
 		return this.request(endpoint, {
 			method: 'PUT',
 			headers: {
@@ -71,7 +71,7 @@ export class ApiClient {
 		});
 	}
 
-	async patch(endpoint: string, data: any): Promise<Response> {
+	async patch(endpoint: string, data: unknown): Promise<Response> {
 		return this.request(endpoint, {
 			method: 'PATCH',
 			headers: {