Make the resume bilingual and part of the shared site chrome

Adds a Russian version (data/resume.ru.json, default language) with an RU/EN
switch stored under the key shared with the front page and the portfolio.
The top bar becomes the site-wide one (brand, Resume, Portfolio, Gitea,
Contact, language, theme) with a second row of anchors for this page's
sections, and the fonts move to Unbounded and Onest so the three pages share
one type system. Portfolio links now point at /portfolio/.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XtcZtnG4GQA1d6mW5PNrS9

components/LangSwitch.tsx

@@ -0,0 +1,31 @@
+'use client'
+
+import { useLang } from '@/lib/useLang'
+import type { Lang } from '@/lib/i18n'
+import styles from './topbar.module.css'
+
+/** RU / EN switch. The choice is stored under the key shared with the rest of shanaty.ru. */
+export default function LangSwitch() {
+  const lang = useLang()
+  const choose = (next: Lang) => {
+    const html = document.documentElement
+    html.dataset.lang = next
+    html.lang = next
+    document.title = html.getAttribute(`data-title-${next}`) ?? document.title
+    try {
+      localStorage.setItem('lang', next)
+    } catch {
+      // Storage can be blocked; the language still changes for this visit.
+    }
+    window.dispatchEvent(new Event('langchange'))
+  }
+  return (
+    <div className={styles.seg} role="group" aria-label={lang === 'ru' ? 'Язык' : 'Language'}>
+      {(['ru', 'en'] as const).map((code) => (
+        <button key={code} type="button" aria-pressed={lang === code} onClick={() => choose(code)}>
+          {code.toUpperCase()}
+        </button>
+      ))}
+    </div>
+  )
+}