Various build shenenigans (#5)

This PR extends the build pipeline of the www service to support
locale-prefixed static builds (EN/RU) with build-time SSG output
injection, while also refactoring UI typography to a tokenized Tailwind
v4 @theme-driven approach.

Changes:

- Add build-time SSG plugin to @ermnvldmr/rsbuild-config and wire
multi-locale builds (/en/, /ru/) into services/www.
- Introduce new @ermnvldmr/i18n package (locale constants, path helpers,
keysets, pluralization) and apply it to www navigation/text.
- Refactor ui typography to a shared getTypographyClassNames utility +
Tailwind token definitions, with stl/cn updated for correct
Tailwind-merge behavior.

ci/config/nginx/default.conf

@@ -2,9 +2,6 @@ server {
     listen 80;
     server_name localhost;
 
-    root /usr/share/nginx/html;
-    index index.html;
-
     # Gzip compression
     gzip on;
     gzip_vary on;
@@ -12,20 +9,41 @@ server {
     gzip_comp_level 6;
     gzip_types text/plain text/css text/xml application/json application/javascript application/rss+xml application/atom+xml image/svg+xml;
 
-    # Clean URLs (remove .html from URI)
-    location / {
-        try_files $uri $uri/ $uri.html /index.html;
+    # Root redirect: detect browser language, fallback to /en/
+    location = / {
+        set $locale "en";
+        if ($http_accept_language ~* "(^|,\s*)ru") {
+            set $locale "ru";
+        }
+        return 302 /$locale/;
     }
 
-    # Cache static assets
-    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
+    # English locale
+    location /en/ {
+        alias /usr/share/nginx/html/en/;
+        index index.html;
+        try_files $uri $uri/ $uri.html /en/index.html;
+    }
+
+    # Russian locale
+    location /ru/ {
+        alias /usr/share/nginx/html/ru/;
+        index index.html;
+        try_files $uri $uri/ $uri.html /ru/index.html;
+    }
+
+    # Cache hashed static assets (JS, CSS, fonts)
+    location ~* \.(js|css|woff|woff2|ttf|eot)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    # Cache images
+    location ~* \.(png|jpg|jpeg|gif|ico|svg)$ {
         expires 1y;
         add_header Cache-Control "public, no-transform";
     }
 
     # Error pages
-    error_page 404 /404.html;
-    location = /404.html {
-        internal;
-    }
+    error_page 404 /en/index.html;
 }

ci/docker/www/Dockerfile

@@ -16,6 +16,7 @@ COPY packages/rsbuild-config/package.json ./packages/rsbuild-config/
 COPY packages/stl/package.json ./packages/stl/
 COPY packages/storybook-config/package.json ./packages/storybook-config/
 COPY packages/ui/package.json ./packages/ui/
+COPY packages/i18n/package.json ./packages/i18n/
 COPY services/www/package.json ./services/www/
 
 # Install dependencies
@@ -27,10 +28,11 @@ COPY . .
 # Build dependencies
 RUN pnpm --filter @ermnvldmr/rsbuild-config build
 RUN pnpm --filter @ermnvldmr/stl build
+RUN pnpm --filter @ermnvldmr/i18n build
 RUN pnpm --filter @ermnvldmr/ui build
 
-# Build the website
-RUN pnpm --filter @ermnvldmr/www build
+# Build the website (all locales)
+RUN pnpm --filter @ermnvldmr/www build:all
 
 # Stage 2: Runtime
 FROM nginx:alpine