feat: series-таксономия, переключатель темы вправо, соцсети в меню

- hugo.toml: [taxonomies] series = "series"; [params.socialIcons] (github, telegram, rss)
- layouts/partials/series_nav.html: модуль «Серия: N из M» с навигацией prev/next
  (сортировка по series_order), поддержка кириллических названий серий
- layouts/_default/single.html: override темы — подключение series_nav перед контентом
- layouts/partials/extend_footer.html: JS переносит .logo-switches из .logo в конец
  .nav (переключатель темы — справа после меню); server-rendered блок соцсетей
  переносится к меню; иконки — через штатный svg.html темы (github/telegram/rss)
- assets/css/extended/typewriter.css: стили .social-icons-inline, .series-nav;
  .logo-switches после переноса попадает под .nav > .logo-switches (order:2)

Closes openspec change series-taxonomy-and-header

layouts/partials/extend_footer.html

@@ -1,10 +1,14 @@
 {{- /* dedinit() typewriter: animated topics inside logo parens.
        Pure JS + CSS, no Alpine. Progressive enhancement — no-JS keeps
-       the plain "dedinit()" logo. Words configurable via hugo.toml:
-       [params.typewriter] words = ["linux", "llm", "politics"] */ -}}
+       the plain "dedinit()" logo. Words configurable via hugo.toml.
+       Also: moves theme toggle to the right end of .nav and injects
+       social icons (from [params.socialIcons]) next to the menu.
+       Icons are rendered server-side via the theme's svg.html partial. */ -}}
 {{- $tw_words := site.Params.typewriter.words | default (slice "linux" "llm" "politics" "homelab" "nix") -}}
+{{- $social := site.Params.socialIcons | default (slice) -}}
 <script>
 (() => {
+  /* 1) typewriter */
   const LOGO_SEL = 'header .logo a, .logo a';
   const queue = [() => {
     const a = document.querySelector(LOGO_SEL);
@@ -18,21 +22,17 @@
     const box = document.createElement('span');
     box.id = 'dedinit-typewriter';
     box.className = 'tw';
-    box.textContent = '';
     box.appendChild(Object.assign(document.createElement('span'), { className: 'tw-cursor' }));
-    // rebuild: <prefix>(<typewriter>)<suffix>
     a.textContent = '';
     a.appendChild(document.createTextNode(text.slice(0, open + 1)));
     a.appendChild(box);
     a.appendChild(document.createTextNode(text.slice(close)));
 
-    // reduced motion: blink is disabled via CSS; keep typing but no blink
     const TYPE = 90, ERASE = 50, HOLD = 1400, GAP = 400;
     let w = 0, i = 0, dir = 1;
     box.querySelector('.tw-cursor').style.display = 'inline-block';
     const tick = () => {
       const word = words[w];
-      // keep cursor as the last child; typed text goes before it
       box.replaceChildren(document.createTextNode(word.slice(0, i)), box.querySelector('.tw-cursor'));
       let delay;
       if (dir === 1) {
@@ -46,7 +46,45 @@
     };
     tick();
   }];
-  if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', () => queue.shift()());
-  else queue.shift()();
+
+  /* 2) move theme toggle (logo-switches) to the end of .nav, after #menu.
+        It is nested inside .logo in the theme; appending to .nav moves it
+        visually to the far right (flex order handled by CSS). */
+  const toggleQueue = [() => {
+    const nav = document.querySelector('header .nav, .nav');
+    const sw = nav && nav.querySelector('.logo-switches');
+    if (!nav || !sw || sw.dataset.moved) return;
+    sw.dataset.moved = '1';
+    nav.appendChild(sw);
+  }];
+
+  /* 3) social icons: a hidden server-rendered container is moved into nav
+        next to the menu. The icons are rendered by Hugo (theme svg.html),
+        so no client-side icon data is needed. */
+  const socialQueue = [() => {
+    const nav = document.querySelector('header .nav, .nav');
+    const box = document.getElementById('__social-icons');
+    if (!nav || !box) return;
+    box.id = '';
+    const menu = nav.querySelector('#menu');
+    if (menu) menu.after(box);
+    else nav.appendChild(box);
+  }];
+
+  const run = () => { queue.shift()(); toggleQueue.shift()(); socialQueue.shift()(); };
+  if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', run);
+  else run();
 })();
-</script>
+</script>
+{{- /* server-rendered social icons; moved into the nav by the JS above.
+       display:none so no-JS visitors never see a stray block. */ -}}
+{{- if $social -}}
+<div id="__social-icons" class="social-icons-inline" style="display:none">
+  {{- range $social -}}
+  <a href="{{ trim .url " " | safeURL }}" target="_blank" rel="noopener noreferrer me"
+     title="{{ (.title | default .name) | title }}" class="social-icon">
+    {{- partial "svg.html" . -}}
+  </a>
+  {{- end -}}
+</div>
+{{- end -}}