ui: restore a 50px top header with centered brand; rename to CoRE.Vizion+

Re-add the top header as a 50px bar injected by ensureHeader() on every
layout page (skipped on login), with the brand centered. The layout height
now subtracts both header and footer. Rebrand the project CoRE.Vision →
CoRE.Vizion+ everywhere: header + footer brand, all page <title>s, the login
card, and the FastAPI OpenAPI title (applies on next backend restart).

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

frontend/static/app.js

@@ -144,13 +144,21 @@ function ensureFooter() {
   if (document.querySelector("footer.app-footer") || !document.querySelector(".layout")) return;
   const f = document.createElement("footer");
   f.className = "app-footer";
-  f.innerHTML = `<span class="brand">CoRE<span>.Vision</span></span>` +
+  f.innerHTML = `<span class="brand">CoRE<span>.Vizion+</span></span>` +
                 `<span class="spacer"></span>` +
                 `<span class="stats" id="sys-stats"></span>` +
                 `<span class="clock" id="clock"></span>` +
                 `<span id="footer-version"></span>`;
   document.body.appendChild(f);
 }
+function ensureHeader() {
+  // шапка 50px сверху с брендом по центру — на страницах с раскладкой (не на login)
+  if (document.querySelector("header.app-header") || !document.querySelector(".layout")) return;
+  const h = document.createElement("header");
+  h.className = "app-header";
+  h.innerHTML = `<span class="brand">CoRE<span>.Vizion+</span></span>`;
+  document.body.insertBefore(h, document.body.firstChild);
+}
 async function refreshStats() {
   const el = document.getElementById("sys-stats");
   try {
@@ -2112,6 +2120,7 @@ function initTabs() {
 // ── загрузка страницы ───────────────────────────────────────────
 document.addEventListener("DOMContentLoaded", async () => {
   ensureVersionEl();
+  ensureHeader();                 // шапка 50px с брендом по центру
   ensureFooter();                 // создаёт футер с #sys-stats/#clock до их заполнения
   startClock();
   bindLogout();