fix: harden v2 custom widgets and Workshop (#6480)

packages/definitions/src/docs/index.ts

@@ -1,6 +1,15 @@
 import type { HomarrDocumentationPath } from "./homarr-docs-sitemap";
 
-const documentationBaseUrl = "https://homarr.dev";
+const defaultDocumentationBaseUrl = "https://homarr.dev";
+
+const getDocumentationBaseUrl = () => {
+  const browserValue =
+    typeof document === "undefined"
+      ? undefined
+      : document.querySelector<HTMLMetaElement>('meta[name="homarr-website-url"]')?.content;
+  const serverValue = typeof process === "undefined" ? undefined : process.env.HOMARR_WEBSITE_URL;
+  return (browserValue || serverValue || defaultDocumentationBaseUrl).replace(/\/+$/u, "");
+};
 
 // Please use the method so the path can be checked!
 export const createDocumentationLink = (
@@ -8,7 +17,7 @@ export const createDocumentationLink = (
   hashTag?: `#${string}`,
   queryParams?: Record<string, string>,
 ) => {
-  const url = `${documentationBaseUrl}${path}`;
+  const url = `${getDocumentationBaseUrl()}${path}`;
   const params = queryParams ? `?${new URLSearchParams(queryParams)}` : "";
   return `${url}${params}${hashTag ?? ""}`;
 };