server/nextcloud: Allow configuring files_chunk_size and setup linked limits

- linked settings are (configured to same value appending some overheads):
   - nginx_max_size
   - php_post_max_size
   - php_upload_max_size

roles/server/nextcloud/defaults/main.yml

@@ -34,8 +34,13 @@ nextcloud_admin_user: "admin"
 nextcloud_admin_pass: "{{ lookup('password', 'credentials/' + inventory_hostname + '/' + domain + '/' + nextcloud_admin_user + ' length=80') }}"
 
 default_phone_region: "DE"
+files_chunk_size: "{{ 10 * 1024 * 1024 }}" # bytes
 reset_password_link: "disabled" # "" means internal enabled, "disabled" means disabled, <link> means using this link
 
+nginx_max_size: "{{ php_post_max_size|int + 4 * 1024 }}" # appending encryption overhead
+php_post_max_size: "{{ php_upload_max_size|int + 4 * 1024 }}" # appending HTTP overhead
+php_upload_max_size: "{{ files_chunk_size|int + 16 * 1024 }}" # appending internal overhead
+
 import_config:
   system:
     # domain
@@ -60,6 +65,9 @@ import_config:
       port: 0
     # user experience
     default_phone_region: "{{ default_phone_region }}"
+  apps:
+    files:
+      max_chunk_size: "{{ files_chunk_size }}"
 
 enabled_apps_list:
   - accessibility

roles/server/nextcloud/meta/main.yml

@@ -22,6 +22,8 @@ dependencies:
       - "{{ nextcloud_installation_directory }}/apps"
     admin_values:
       memory_limit: 1G
+      post_max_size: "{{ php_post_max_size }}"
+      upload_max_size: "{{ php_upload_max_size }}"
   - role: redis/instance
     # domain
     # system_user
@@ -42,7 +44,7 @@ dependencies:
       rewrite ^/.well-known/host-meta /public.php?service=host-meta last;
       rewrite ^/.well-known/host-meta.json /public.php?service=host-meta-json last;
       rewrite ^/.well-known/webfinger /public.php?service=webfinger last;
-      client_max_body_size 10240M;
+      client_max_body_size {{ nginx_max_size }};
       #fastcgi_buffers 64 4K;
       location / {
         rewrite ^ /index.php;