Language selector: move it into the visible top bar on every page that loads lang.js

The EN | DE | ES switcher existed but rendered into the footer slot, so a
visitor had to scroll to the bottom of the page to find it (measured live:
y=5582 on /, y=5498 on /odoo-erp-automation-bootcamp/). The user asked for a
selector a visitor can actually see.

- index.html, de/index.html, es/index.html: the slot is now the first child of
  .hero .container, right-aligned in flow above the kicker. In flow, not a
  fixed pill, so it cannot collide with the absolute .hero-notice.
- odoo-erp-automation-bootcamp/index.html: the slot is now the last child of
  .bc-topbar .container, right of the nav links, behind a hairline brass
  divider; .bc-topbar-links gets margin-left:auto so the brand stays left.
- One [data-lang-switcher] per page; the footer slot is removed everywhere.
- Styling follows the CI: Inter 12px / .06em / uppercase codes (the existing
  .lang-switch rules), active language in --brass on these midnight surfaces,
  the other two in the surrounding text colour. CSS-only, in each page's
  inline <style>; lang.js is untouched, so its redirect behaviour is unchanged.
- The rules are recorded in work/i18n/I18N-BUILD-PLAN.md §3 for the phase-2
  pages (de|es/odoo-hosting-2027.html, de|es/support.html).

odoo-erp-automation-bootcamp/index.html

@@ -76,6 +76,29 @@
       .bc-topbar-links a:hover {
         color: var(--brass);
       }
+      /* Language selector — slides into the top-bar row, right of the links, behind a hairline brass divider.
+         CI §1/§2: brass marks the active language; lang.js owns the markup. */
+      .bc-topbar-links {
+        margin-left: auto;
+      }
+      .bc-topbar .lang-switch-slot {
+        display: flex;
+        align-items: center;
+        padding-left: 1rem;
+        border-left: 1px solid rgba(201, 162, 39, 0.45);
+      }
+      .bc-topbar .lang-switch {
+        color: rgba(255, 255, 255, 0.7);
+      }
+      .bc-topbar .lang-switch a:hover,
+      .bc-topbar .lang-switch a:focus-visible {
+        color: var(--brass-bright);
+      }
+      .bc-topbar .lang-switch a[aria-current="true"] {
+        color: var(--brass);
+        text-decoration: underline;
+        text-underline-offset: 3px;
+      }
 
       /* Hero */
       .bc-hero {
@@ -484,6 +507,7 @@
           <a href="/index.html#pricing">Plans &amp; pricing</a>
           <a href="/support.html">Support</a>
         </nav>
+        <div data-lang-switcher class="lang-switch-slot"></div>
       </div>
     </div>
 
@@ -788,7 +812,6 @@
         </div>
         <div class="fcopy">Copyright &copy; ODOO4projects LLC</div>
       </div>
-      <div data-lang-switcher class="lang-switch-slot"></div>
     </footer>
     <script defer src="/static/lang.js"></script>
   </body>