refactoring: 'Datei zu Vorgang hinzufügen' an DB angepasst

src/routes/(angemeldet)/upload/+page.svelte

@@ -152,40 +152,33 @@
 	}
 
 	// `/(angemeldet)/view` return true or false
-	async function case_exists(case_no) {
+	async function case_exists(case_name: string) {
 
-		if (case_no == '') {
+		if (case_name == '') {
 			zugangscode = zugangscode_old;
+			return;
 		}
 
-		// ping `/view` with caseNumber in POST body
-		let url = '/view';
+		let url = `/api/list/${case_name}`
 
-		let data = new FormData();
-		data.append('caseNumber', case_no);
+		const response = await fetch(url, { method: 'HEAD'});
+		const status = response.status;
 
-		// fetch code in parallel
-		const code = await get_code(case_no);
-		if (code != -1) {
-			zugangscode = code;
+		if (status == 200) {
 			case_existing = true;
+			const code = await get_code(case_name);
+			zugangscode = code;
+
 			return true
-		}
 
-		const response = await fetch(url, { method: 'POST', body: data });
-
-		const res_json = await response.json();
-		const status = res_json.status;
-
-		if (status != 303) {
+		} else {
 			case_existing = false;
 			zugangscode = zugangscode_old;
+			return false
 		}
-
-		return false;
 	}
 
-	async function get_code(case_no) {
+	async function get_code(case_no: string) {
 
 		if (case_no == '') return;