Add GDPR cookie-consent banner (Consent Mode v2)

- consent.js: self-contained, non-blocking bottom banner in EN/MK/SI,
  remembers the choice in localStorage, links to the per-language cookie
  policy. Accept -> gtag consent 'update' granted; Decline stays denied.
- Head GA snippet restores a returning visitor's prior "granted" choice
  before the first hit; loads /consent.js on every page.
- Re-openable via window.msosOpenConsent() for a "manage cookies" link.

Verified in-browser: shows for new visitors, Accept grants + remembers,
reload keeps consent without re-prompting, Slovene text + /si/ policy link.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

si/get-to-know-slovenia/a-first-taste-of-slovenian-food/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Začnimo s štruklji, joto, žlikrofi, friko, bogračem in potico. Skupaj pokažejo kuhinjo, ki jo oblikujejo pokrajine in ne en sam jedilnik.">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/a-first-taste-of-slovenian-food/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/a-first-taste-of-slovenian-food/">

si/get-to-know-slovenia/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Slovenija je na zemljevidu morda majhna, vendar se med Alpami, Jadransko obalo, zelenimi rekami, starimi mesti in mirnimi kotički skriva veliko. V teh zgodbah…">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/">

si/get-to-know-slovenia/lake-bled-beyond-the-famous-view/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Otok je podoba, ki jo poznajo vsi. Pravi značaj Bleda se pokaže, ko obhodimo jezero in pustimo, da se razgled ves čas spreminja.">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/lake-bled-beyond-the-famous-view/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/lake-bled-beyond-the-famous-view/">

si/get-to-know-slovenia/ljubljana-through-our-eyes/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Ne popoln vodnik po mestu, ampak zbirka krajev in navad, skozi katere smo se mnogi začeli počutiti domače.">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/ljubljana-through-our-eyes/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/ljubljana-through-our-eyes/">

si/get-to-know-slovenia/slovenian-habits-that-may-surprise-you/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Ne pravila, ki bi opisovala vse ljudi, ampak drobni vzorci, ki smo jih mnogi opazili med spoznavanjem vsakdanjega življenja.">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/slovenian-habits-that-may-surprise-you/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/slovenian-habits-that-may-surprise-you/">

si/get-to-know-slovenia/slovenias-stories-in-stone-and-tradition/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Dediščina ni le grad ali muzej. Lahko je most, ki ga uporabljamo vsak dan, reka, ki izgine pod zemljo, rudarsko mesto, oblikovano z živim srebrom, ali znanje…">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/slovenias-stories-in-stone-and-tradition/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/slovenias-stories-in-stone-and-tradition/">

si/get-to-know-slovenia/welcome-to-slovenia/index.html

@@ -14,9 +14,14 @@
         ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied',
         analytics_storage: 'denied', wait_for_update: 500
       });
+      // Restore a returning visitor's prior choice before the first hit.
+      try { if (localStorage.getItem('msos-consent') === 'granted') {
+        gtag('consent', 'update', { ad_storage:'granted', ad_user_data:'granted',
+          ad_personalization:'granted', analytics_storage:'granted' }); } } catch(e){}
       gtag('js', new Date());
       gtag('config', 'G-WVYV807VSS');
     </script>
+    <script src="/consent.js" defer></script>
     <meta name="description" content="Majhna dežela številnih pokrajin, tihih odkritij in krajev, ki sčasoma postanejo domači.">
     <link rel="canonical" href="https://msosorg.com/si/get-to-know-slovenia/welcome-to-slovenia/">
     <link rel="alternate" hreflang="en" href="https://msosorg.com/en/get-to-know-slovenia/welcome-to-slovenia/">