feat: uniform system.content source schema across installers and repositories

roles/bootstrap/tasks/debian.yml

@@ -43,7 +43,10 @@
         debootstrap --keyring=/usr/share/keyrings/debian-archive-keyring.gpg
         --include={{ bootstrap_debian_base_csv }}
         {{ bootstrap_debian_release }} /mnt
-        {{ system_cfg.mirror | default('http://deb.debian.org/debian', true) }}
+        {{ system_cfg.content.url }}
+      environment:
+        http_proxy: "{{ system_cfg.content.proxy }}"
+        https_proxy: "{{ system_cfg.content.proxy }}"
       register: bootstrap_debian_base_result
       changed_when: bootstrap_debian_base_result.rc == 0
 
@@ -60,6 +63,10 @@
           Acquire::Retries "3";
           Acquire::http::Pipeline-Depth "10";
           APT::Install-Recommends "false";
+          {% if system_cfg.content.proxy | length > 0 %}
+          Acquire::http::Proxy "{{ system_cfg.content.proxy }}";
+          Acquire::https::Proxy "{{ system_cfg.content.proxy }}";
+          {% endif %}
         mode: "0644"
 
     - name: Update package lists