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/components/shared/export-markdown-button.tsx

@@ -1,5 +1,6 @@
 "use client";
 
+import { useState } from "react";
 import { Copy, Download, FileDown } from "lucide-react";
 import { toast } from "sonner";
 import { useTranslations } from "next-intl";
@@ -11,15 +12,46 @@ import {
   DropdownMenuTrigger,
 } from "@/components/ui/dropdown-menu";
 import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from "@/components/ui/tooltip";
+import { UpgradeDialog } from "@/components/premium/upgrade-dialog";
+import { ProBadge } from "@/components/premium/pro-badge";
 
 export function ExportMarkdownButton({
   markdown,
   filename,
+  locked = false,
 }: {
   markdown: string;
   filename: string;
+  locked?: boolean;
 }) {
   const t = useTranslations("common");
+  const [upgradeOpen, setUpgradeOpen] = useState(false);
+
+  if (locked) {
+    return (
+      <>
+        <TooltipProvider>
+          <Tooltip>
+            <TooltipTrigger render={
+              <Button variant="ghost" size="icon" aria-label={t("exportMarkdown")} onClick={() => setUpgradeOpen(true)}>
+                <FileDown className="h-4 w-4" />
+              </Button>
+            } />
+            <TooltipContent className="flex items-center gap-1.5">
+              {t("exportMarkdown")}
+              <ProBadge />
+            </TooltipContent>
+          </Tooltip>
+        </TooltipProvider>
+        <UpgradeDialog
+          open={upgradeOpen}
+          onOpenChange={setUpgradeOpen}
+          featureKey="markdown_export"
+          featureLabel="Markdown export"
+        />
+      </>
+    );
+  }
 
   async function handleCopy() {
     try {