Improve schema and update tags

- Make constants in schema explicit
- Enumerate tag-categories
- More i18n utilities
- Better anonymous user support without special field
- Remove most tuples and unchecked type-casting

src/components/UserComponent.astro

@@ -1,5 +1,5 @@
 ---
-import { type CollectionEntry, getEntry } from "astro:content";
+import { type CollectionEntry } from "astro:content";
 import { type Lang } from "../content/config";
 import { getUsernameForLang } from "../utils/get_username_for_lang";
 
@@ -9,13 +9,10 @@ type Props = {
 };
 
 let { user, lang } = Astro.props;
-if (user.data.isAnonymous) {
-  user = await getEntry("users", "anonymous");
-}
 const username = getUsernameForLang(user, lang);
 let link: string | null = null;
 if (user.data.preferredLink) {
-  const preferredLink = user.data.links[user.data.preferredLink] as string | [string, string];
+  const preferredLink = user.data.links[user.data.preferredLink]!;
   if (typeof preferredLink === "string") {
     link = preferredLink;
   } else {
@@ -25,11 +22,11 @@ if (user.data.preferredLink) {
 ---
 
 {
-  user.data.isAnonymous || !user.data.preferredLink ? (
-    <span>{username}</span>
-  ) : (
+  link ? (
     <a href={link} class="text-link underline" target="_blank">
       {username}
     </a>
+  ) : (
+    <span>{username}</span>
   )
 }