Stop overriding page title and #site-title with siteName (AI)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

strings/cs.json

@@ -1,5 +1,4 @@
 {
-  "siteName": "Ukázkový blog",
   "appStartError": "Blog se nepodařilo spustit: {message}",
   "articleNotFound": "Článek nebyl nalezen",
 

strings/en.json

@@ -1,5 +1,4 @@
 {
-  "siteName": "Example Blog",
   "appStartError": "Failed to start the blog: {message}",
   "articleNotFound": "Article not found",
 

strings/sk.json

@@ -1,5 +1,4 @@
 {
-  "siteName": "Ukážkový blog",
   "appStartError": "Blog sa nepodarilo spustiť: {message}",
   "articleNotFound": "Článok nebol nájdený",