i18n: build-time ru/en localization + EN homepage & cookie-policy

- build-pages.mjs: per-locale page/partial overrides (*.en.html), i18n token
  resolution with ru fallback, <html lang> + assetPrefix per locale
- UI dictionaries src/i18n/{ru,en}.json; lang-switch partial
- headers/footer/partials converted to {{i18n:…}} tokens
- root-absolute static asset refs so /en/ subpath loads css/js/vendor
- EN content: homepage (index.en.html + partials) and cookie-policy.en.html
  (cookie-policy body translated via apinex.bond /v1/tools/translator)

src/partials/mini-projects-section.html

@@ -29,7 +29,7 @@
                 <div class="mp-card__media" aria-hidden="true">
                   <img
                     class="mp-card__image"
-                    src="assets/misc/figma_logo.webp"
+                    src="{{assetPrefix}}assets/misc/figma_logo.webp"
                     alt=""
                     width="800"
                     height="800"
@@ -59,7 +59,7 @@
                 <div class="mp-card__media" aria-hidden="true">
                   <img
                     class="mp-card__image"
-                    src="assets/misc/dribbble_logo.webp"
+                    src="{{assetPrefix}}assets/misc/dribbble_logo.webp"
                     alt=""
                     width="1024"
                     height="1024"
@@ -89,7 +89,7 @@
                 <div class="mp-card__media" aria-hidden="true">
                   <img
                     class="mp-card__image"
-                    src="assets/misc/tg-channel-logo-design_not_pizza.webp"
+                    src="{{assetPrefix}}assets/misc/tg-channel-logo-design_not_pizza.webp"
                     alt=""
                     width="640"
                     height="640"