Link Impressum's seller identity to company-settings, not hand-typed prose

"Angaben zum Anbieter"/"Umsatzsteuer"/"Handelsregister"/"Geschäftsführung"/
"Verantwortlich für den Inhalt" used to be hand-typed into the Impressum's
richText content (seed-legal-pages.ts) with no connection to the same
seller data the invoice PDFs and every email footer already pull from
company-settings — an admin updating one had no reason to remember the
other existed, and the old text was already stale in one concrete way:
it never showed Handelsregister/Geschäftsführung at all even though
company-settings has modeled both since the legal-form work shipped.

Now rendered by a new AnbieterAngaben component, straight from
getCompanySettings(), positioned above the CMS richText (which keeps
only genuinely editorial content: Kontakt, Haftung für Inhalte, Haftung
für Links, Urheberrecht). Same "structural/brand elements in code, only
pull the actual numbers/copy that need single-sourcing from data"
pattern this page's own Nachhaltigkeit sidebar card already used.

RichText.tsx's headingId() is now exported so the new block's headings
get the exact same id-assignment logic as CMS-driven ones, keeping the
SectionTOC sidebar's ids in sync with both sources.

/impressum moves from static to dynamic rendering (it now fetches live
company-settings data, cache: "no-store") — an acceptable tradeoff for
a legally-required page to never show stale seller info.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/components/RichText.tsx

@@ -35,7 +35,13 @@ function plainText(node: LexicalNode): string {
 // "section-1" id from the leading number — immune to copy edits changing
 // the heading text later, unlike a text-derived slug. Anything else
 // (headings with no leading number) falls back to a plain slugify.
-function headingId(text: string): string {
+// Exported — the Impressum page renders some of its own headings outside
+// this CMS-driven richText (the "Angaben zum Anbieter"/"Umsatzsteuer"/
+// "Verantwortlich für den Inhalt" sections come straight from
+// company-settings, not the richText field, see app/impressum/page.tsx)
+// and needs the exact same id-assignment logic so its SectionTOC entries
+// actually match the ids those headings render with.
+export function headingId(text: string): string {
   const numbered = text.match(/^(\d+)\./);
   if (numbered) return `section-${numbered[1]}`;
   return text