Upgrade to drive v0.25.3, replace MinIO with RustFS

- use rustfs instead of minio and provide migration script
- Schedule clean_pending_items/purge_deleted_items with celery beat
- Give celery workers the S3 access key secret
- Collabora admin access needs setting a password

Following the [C4DT AI Policy](https://git.coopcloud.tech/c4dt/ai-policy/src/branch/main/AI-POLICY.md):

 #LLM_vibe
 #LLM_model Claude Opus 5.5

- [x] I take full responsibility for this code
- [x] I understand every line of this code
- [x] I tested this code thoroughly on my own computer / servers
- [x] None of the commit messages were created using LLMs
- [x] I will participate in any discussion on my own and will not use an LLM for the discussion

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

abra.sh

@@ -1,11 +1,12 @@
 # Set any config versions here
 # Docs: https://docs.coopcloud.tech/maintainers/handbook/#manage-configs
-export ABRA_ENTRYPOINT_VERSION=v11
-export NGINX_CONF_VERSION=v6
-export ONLYOFFICE_CONF_VERSION=v2
+export ABRA_ENTRYPOINT_VERSION=v12
+export NGINX_CONF_VERSION=v7
+export ONLYOFFICE_CONF_VERSION=v3
 export PG_BACKUP_VERSION=v4
 export MIGRATE_VERSION=v1
-export MINIO_INITIALIZE_VERSION=v2
+export S3_INITIALIZE_VERSION=v1
+export MIGRATE_FROM_MINIO_VERSION=v1
 
 environment() {
   # this exports all the secrets as environment variables
@@ -16,8 +17,13 @@ migrate() {
   /migrate.sh
 }
 
-minio_initialize() {
-  /minio-initialize.sh
+s3_initialize() {
+  /s3-initialize.sh
+}
+
+# only available when deployed with compose.minio-migration.yml
+migrate_from_minio() {
+  /migrate-from-minio.sh "$@"
 }
 
 trigger_wopi() {