Show the own site icon to Google under every address, and the KANTARCI landing page

- Google kept showing the KantSites K for Elektro Bernhard after the site
  icon was changed. The own icon only existed at 32 and 180 px, and Google
  takes multiples of 48 only; /favicon.svg was a file in public/, so the web
  server always delivered the bundled K.
- The icon is now also cut at 48 and 192 px. The head links /favicon-192.png,
  /favicon.ico serves the 48 px PNG, and /favicon.svg is answered by the
  application: the bundled mark without an own icon (now in
  public/assets/favicon.svg), otherwise a 302 to the 192 px PNG. Sites that
  set their icon earlier get the new sizes on first request. A removed icon
  no longer counts even though its files remain.
- The archive update only adds files to public/, so it now deletes the old
  public/favicon.svg explicitly.
- Seventh local reference site: the KANTARCI Immobilien landing page with a
  three-step rental request, own database, seed and reset scripts.

Tests: 582 PHPUnit on PHP 8.2 and 8.4, 35 node, test:editor and
test:browser green (test:browser reports only the known editor colour
contrast on /grundlagen).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.claude/launch.json

@@ -108,6 +108,26 @@
         "$env:APP_ENV='prod'; $env:APP_DEBUG='0'; $env:DATABASE_URL='sqlite:///C:/Django Project/KantSites/var/immobilien-deeg.db'; $env:MEDIA_DIRECTORY='C:/Django Project/KantSites/var/immobilien-deeg-media'; $env:SITE_ORIGIN='http://127.0.0.1:8095'; & C:/php84/php.exe -d upload_max_filesize=8M -d post_max_size=10M -d memory_limit=256M -S 127.0.0.1:8095 -t public bin/dev-router.php"
       ],
       "port": 8095
+    },
+    {
+      "name": "kantarci-immobilien",
+      "runtimeExecutable": "powershell",
+      "runtimeArgs": [
+        "-NoProfile",
+        "-Command",
+        "$env:APP_ENV='dev'; $env:DATABASE_URL='sqlite:///C:/Django Project/KantSites/var/kantarci-immobilien.db'; $env:MEDIA_DIRECTORY='C:/Django Project/KantSites/var/kantarci-immobilien-media'; $env:SITE_ORIGIN='http://127.0.0.1:8098'; & C:/php84/php.exe -d upload_max_filesize=8M -d post_max_size=10M -d memory_limit=256M -S 127.0.0.1:8098 -t public bin/dev-router.php"
+      ],
+      "port": 8098
+    },
+    {
+      "name": "kantarci-immobilien-prod",
+      "runtimeExecutable": "powershell",
+      "runtimeArgs": [
+        "-NoProfile",
+        "-Command",
+        "$env:APP_ENV='prod'; $env:APP_DEBUG='0'; $env:DATABASE_URL='sqlite:///C:/Django Project/KantSites/var/kantarci-immobilien.db'; $env:MEDIA_DIRECTORY='C:/Django Project/KantSites/var/kantarci-immobilien-media'; $env:SITE_ORIGIN='http://127.0.0.1:8099'; & C:/php84/php.exe -d upload_max_filesize=8M -d post_max_size=10M -d memory_limit=256M -S 127.0.0.1:8099 -t public bin/dev-router.php"
+      ],
+      "port": 8099
     }
   ]
 }