fix: standardize locked-vs-hidden treatment across all 9 per-tier gated features (v0.79.0)

Rule, applied consistently everywhere via a new isFeatureAvailableAnyTier() helper: if a feature is enabled on at least one tier, it stays visible for locked-out viewers with a small "Pro" badge and opens an upgrade prompt on click; if a feature is disabled on every tier, it hides entirely, since there's no upgrade path to point at.

Covers: recipe variations, meal/drink pairings, nutrition estimation, Markdown export (5 call sites), weekly nutrition, import from URL, import from photo, and the Instacart grocery-delivery menu item. Previously inconsistent — some hid outright, one showed a lock icon overlapping its own icon.

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

apps/web/app/(app)/pantry/page.tsx

@@ -10,7 +10,7 @@ import { ExpiringLeftovers } from "@/components/pantry/expiring-leftovers";
 import { scoreRecipesAgainstPantry } from "@/lib/pantry-match";
 import { dishExpiresAt, daysUntil, isLeftoverExpiringSoon } from "@/lib/leftover-match";
 import { getPublicUrl } from "@/lib/storage";
-import { getFeatureFlagMatrix, type Tier } from "@/lib/feature-flags";
+import { getFeatureFlagMatrix, isFeatureAvailableAnyTier, type Tier } from "@/lib/feature-flags";
 
 export const metadata: Metadata = {};
 
@@ -18,7 +18,9 @@ export default async function PantryPage() {
   const session = await auth.api.getSession({ headers: await headers() });
   if (!session) return null;
   const viewerTier = (session.user as { tier?: string }).tier as Tier | undefined ?? "free";
-  const canExportMarkdown = (await getFeatureFlagMatrix()).markdown_export[viewerTier];
+  const featureFlags = await getFeatureFlagMatrix();
+  const markdownExportLocked = !featureFlags.markdown_export[viewerTier];
+  const markdownExportAvailable = isFeatureAvailableAnyTier(featureFlags, "markdown_export");
 
   const [items, candidateRecipes, cookedDishes] = await Promise.all([
     db.query.pantryItems.findMany({
@@ -78,7 +80,7 @@ export default async function PantryPage() {
 
   return (
     <div className="space-y-6">
-      <PantryPageHeader items={mappedItems} canExportMarkdown={canExportMarkdown} />
+      <PantryPageHeader items={mappedItems} markdownExportAvailable={markdownExportAvailable} markdownExportLocked={markdownExportLocked} />
       <ExpiringLeftovers leftovers={leftovers} />
       <ExpiringSoonSuggestions suggestions={suggestions} />
       <PantryManager key={mappedItems.map((i) => i.id).join(",")} initialItems={mappedItems} />