Adapt deployment for Dokploy

Replace the Gitea Actions SSH deploy with a Docker image
(serversideup/php fpm-nginx) and docker-compose setup. Store the
SQLite database inside the persistent storage volume, trust the
reverse proxy, and move admin credentials into config so they work
with cached configuration.

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

docker/entrypoint.d/10-prepare-storage.sh

@@ -0,0 +1,19 @@
+#!/bin/sh
+# storage монтируется как volume: при пустом томе создаём нужную структуру и файл SQLite
+set -e
+
+cd /var/www/html
+
+mkdir -p \
+    storage/app/public \
+    storage/app/private \
+    storage/framework/cache/data \
+    storage/framework/sessions \
+    storage/framework/testing \
+    storage/framework/views \
+    storage/logs \
+    storage/database
+
+if [ "${DB_CONNECTION:-sqlite}" = "sqlite" ] && [ -n "${DB_DATABASE:-}" ] && [ ! -f "$DB_DATABASE" ]; then
+    touch "$DB_DATABASE"
+fi