Actually commit api-client-php's vendor/ - it was silently gitignored

omsorgCore/CLAUDE.md documents vendor/ as committed so the app can run
without a composer install step, but the generator's own .gitignore
(api-client-php/.gitignore) excludes /vendor/ - it only ever existed
untracked on disk locally, which is why the Docker build worked for me
but mitarbeiter-app crashed at runtime on a real (fresh-checkout) deploy:
"Failed opening required '.../api-client-php/vendor/autoload.php'".
Verified by building from a git-archive-simulated fresh checkout with
this fix applied - mitarbeiter-app's login page now renders without the
fatal error.

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

omsorgWeb/mitarbeiter-app/api-client-php/.gitignore

@@ -1,7 +1,12 @@
 # ref: https://github.com/github/gitignore/blob/master/Composer.gitignore
 
 composer.phar
-/vendor/
+
+# vendor/ ist bewusst NICHT ausgeschlossen (Standard-Composer-.gitignore normalerweise schon) -
+# dieser generierte Client wird ohne composer install deployt/containerisiert, siehe
+# omsorgCore/CLAUDE.md "Generierte API-Clients". Nach jedem `generate.sh`-Lauf wird diese Datei
+# vom Generator überschrieben, diese Zeile muss dann jedes Mal erneut entfernt werden (git diff
+# prüfen, analog zum generate-Script in omsorgapp/api-client-ts/package.json).
 
 # Commit your application's lock file https://getcomposer.org/doc/01-basic-usage.md#commit-your-composer-lock-file-to-version-control
 # You may choose to ignore a library lock file http://getcomposer.org/doc/02-libraries.md#lock-file