chore: replace generic email addresses with GitHub references

Replace generic @netresearch.de email addresses with GitHub-native
mechanisms (Issues, Security Advisories, repository URLs).

- Remove email from package metadata (composer.json, ext_emconf.php)
- Add support/issues URLs to package metadata
- Replace security contact with GitHub Security Advisories
- Replace support/contact emails with GitHub Issues links
- Remove email from PHP docblock @author tags
- Use OCI labels in Dockerfiles

Author: CybotTM

src/Model/JsonResponse.php

@@ -13,7 +13,7 @@
  *
  * @category   Netresearch
  *
- * @author     Various Artists <info@netresearch.de>
+ * @author     Various Artists
  * @license    http://www.gnu.org/licenses/agpl-3.0.html GNU AGPl 3
  *
  * @see       http://www.netresearch.de
@@ -30,7 +30,7 @@
  *
  * @category   Netresearch
  *
- * @author     Various Artists <info@netresearch.de>
+ * @author     Various Artists
  * @license    http://www.gnu.org/licenses/agpl-3.0.html GNU AGPl 3
  *
  * @see       http://www.netresearch.de

src/Model/Response.php

@@ -13,7 +13,7 @@
  *
  * @category   Netresearch
  *
- * @author     Various Artists <info@netresearch.de>
+ * @author     Various Artists
  * @license    http://www.gnu.org/licenses/agpl-3.0.html GNU AGPl 3
  *
  * @see       http://www.netresearch.de
@@ -28,7 +28,7 @@
  *
  * @category   Netresearch
  *
- * @author     Various Artists <info@netresearch.de>
+ * @author     Various Artists
  * @license    http://www.gnu.org/licenses/agpl-3.0.html GNU AGPl 3
  *
  * @see       http://www.netresearch.de

src/Util/PhpSpreadsheet/LOReadFilter.php

@@ -9,7 +9,7 @@
  *
  * @category   Netresearch
  *
- * @author     Various Artists <info@netresearch.de>
+ * @author     Various Artists
  * @license    http://www.gnu.org/licenses/agpl-3.0.html GNU AGPl 3
  *
  * @see       http://www.netresearch.de