fix(storefront): align store actions with actual DB schema

Reviewer caught three runtime breakages that the prior commit would
have introduced (the legacy supabase shim masked them by returning
null):

1. **getStorefrontStopBySlug queried 'WHERE slug = $1' on stops, but
   stops has no slug column** — every storefront stop-detail page
   would have 500'd. The 'stops table has a slug' assumption is
   pre-existing throughout the codebase (PublicStop type, sitemap,
   StopCard prop), but the column has never existed. Fix: switch the
   route param to the stop's UUID (id). Rename folder [slug] → [id]
   for honesty. Update StopCard prop and the two stops-list links to
   pass stop.id instead of stop.slug. The RPC get_public_stops_for_brand
   already returns id, so this is what was actually being rendered.

2. **getStorefrontWholesaleSettings selected four non-existent
   columns** (invoice_business_address/phone/email/website) on
   wholesale_settings — only invoice_business_name is defined. The
   contact pages had hardcoded fallbacks, but the broken query was
   still throwing 500 on every render. Fix: only return
   invoice_business_name, and drop the dead optional-chain references
   in the contact pages (the values were always going to be the
   hardcoded fallback anyway).

3. **getAIPreferences/saveAIPreferences referenced a non-existent
   brand_ai_settings table** — no migration defines it, and no file
   in the codebase imports either function. Deleted the whole
   preferences.ts module (dead code that would have 500'd the moment
   anyone wired it up).

4. **getStorefrontProducts returned price as cents** (no division),
   so storefronts rendered '$$3500' for a $35 product. Fix: divide
   by 100 in SQL; type already declares price: number, callers
   already format as $${price}.

Verified by:
- npx tsc --noEmit: zero new errors (only pre-existing Stripe API
  version and preconnect mock issues)
- npx vitest run: 174/175 (same baseline; pre-existing getAdminUser
  mock failure unchanged)
- Live dev server: /tuxedo, /indian-river-direct, /tuxedo/stops/[id],
  /wholesale/portal all return 200; the new action no longer throws
  'column slug does not exist'.

src/app/indian-river-direct/stops/IndianRiverStopsList.tsx

@@ -69,7 +69,7 @@ export default function IndianRiverStopsList({ stops, brandName, brandSlug }: Pr
               {upcomingStops.map((stop) => (
                 <Link
                   key={stop.id}
-                  href={`/${brandSlug}/stops/${stop.slug}`}
+                  href={`/${brandSlug}/stops/${stop.id}`}
                   className="stop-card group block bg-white rounded-2xl p-5 shadow-sm ring-1 ring-stone-200/60 transition-all duration-300 hover:shadow-lg hover:ring-orange-200"
                 >
                   <div className="flex flex-col sm:flex-row sm:items-center gap-4">

src/app/indian-river-direct/stops/[id]/page.tsx

@@ -9,7 +9,7 @@ import StopSetEffect from "@/components/storefront/StopSetEffect";
 import StorefrontHeader from "@/components/storefront/StorefrontHeader";
 import StorefrontFooter from "@/components/storefront/StorefrontFooter";
 import LayoutContainer from "@/components/layout/LayoutContainer";
-import { getStorefrontStopBySlug } from "@/actions/storefront";
+import { getStorefrontStopById } from "@/actions/storefront";
 import { formatDate } from "@/lib/format-date";
 
 type Product = {
@@ -53,7 +53,7 @@ export default function StopPage() {
 
   useEffect(() => {
     async function load() {
-      const result = await getStorefrontStopBySlug(slug);
+      const result = await getStorefrontStopById(slug);
       if (!result) return;
 
       setStop(result.stop as unknown as Stop);