feat(docs): version-based docs, correct Gitea tag links, form guide help

- each release now carries a full docs snapshot (reference + handbook)
  under docs/releases/<v>/; the docs frontend loads a version's snapshot
  for /docs/vX.Y.Z/* and shows the handbook/reference of that version
- version dropdown navigates to /docs/<version> (docs home) instead of
  the release notes page; old /docs/vX.Y.Z redirect removed
- generator: --snapshot writes handbook + reference; build copies
  versioned snapshots (last 7 versions) into /docs/versions/<v>/
- fix Gitea tag links: /admin/tool-evaluator/tags/<v> was 404, correct
  URL is /releases/tag/<v>
- add GuideHelp button to forms/pages linking to the matching handbook
  guide (rating, tool add/edit, costs, compare, watchlist, analytics)

artifacts/toolrate/src/pages/compare.tsx

@@ -8,6 +8,7 @@ import { Link, useSearch } from "wouter";
 import { Layout } from "@/components/layout";
 import { useAuth } from "@/hooks/use-auth";
 import { RatingStars } from "@/components/rating-stars";
+import { GuideHelp } from "@/components/guide-help";
 import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Skeleton } from "@/components/ui/skeleton";
@@ -101,7 +102,10 @@ export default function Compare() {
     <Layout>
       <div className="space-y-6 pb-10">
         <div>
-          <h1 className="text-3xl font-bold tracking-tight mb-2">{t("compare.title")}</h1>
+          <h1 className="text-3xl font-bold tracking-tight mb-2 flex items-center gap-2">
+            {t("compare.title")}
+            <GuideHelp guide="vergleichen" label={t("compare.title")} />
+          </h1>
           <p className="text-muted-foreground">{t("compare.subtitle", { count: list.length })}</p>
         </div>