major rework of backend loading and usage:

- split config from user data to config.json, add config.hson.template
- moved default user data localdb to root folder
- moved pve, localdb, ldap backend handlers to backends sub folder
- add dynamic loading of all backends
- add dynamic mapping for auth backends to support multiple auth sources
- update affected endpoints

src/backends/backends.js

@@ -0,0 +1,28 @@
+import path from "path";
+import url from "url";
+
+export default async () => {
+	const backends = {};
+	for (const name in global.config.backends) {
+		// get files and config
+		const target = global.config.backends[name].import;
+		const config = global.config.backends[name].config;
+		// get import path
+		const thisPath = path.dirname(url.fileURLToPath(import.meta.url));
+		const fromPath = path.relative(".", path.dirname(url.fileURLToPath(import.meta.url)));
+		const targetPath = path.relative(".", `${fromPath}/${target}`);
+		const importPath = `./${path.relative(thisPath, targetPath)}`;
+		// import and add to list of imported handlers
+		const Backend = (await import(importPath)).default;
+		backends[name] = new Backend(config);
+		console.log(`backends: initialized backend ${name} from ${importPath}`);
+	}
+	// assign backends to handlers depending
+	const handlers = global.config.handlers;
+	global.pve = backends[handlers.pve];
+	global.db = backends[handlers.db];
+	global.auth = handlers.auth;
+	Object.keys(global.auth).forEach((e) => {
+		global.auth[e] = backends[global.auth[e]];
+	});
+};