feat(infra): add Jellyfin media server configuration and logging support

Add Jellyfin service to ansible inventory with hardware
transcoding and Casdoor SSO configuration. Configure
Alloy syslog listener to capture Jellyfin logs to Loki.
Update documentation with new service mapping and S3
bucket credential retrieval instructions.

ansible/jellyfin/deploy.yml

@@ -0,0 +1,107 @@
+---
+- name: Deploy Jellyfin
+  hosts: ubuntu
+  become: true
+  vars:
+    ansible_python_interpreter: /usr/bin/python3
+  tasks:
+  - name: Check if host has jellyfin service
+    ansible.builtin.set_fact:
+      has_jellyfin: "{{ 'jellyfin' in services | default([]) }}"
+
+  - name: Skip hosts without jellyfin service
+    ansible.builtin.meta: end_host
+    when: not has_jellyfin
+
+  - name: Create jellyfin group
+    ansible.builtin.group:
+      name: "{{ jellyfin_group }}"
+      gid: "{{ jellyfin_gid }}"
+
+  - name: Create jellyfin user
+    ansible.builtin.user:
+      name: "{{ jellyfin_user }}"
+      comment: "Jellyfin service account"
+      group: "{{ jellyfin_group }}"
+      uid: "{{ jellyfin_uid }}"
+      home: "{{ jellyfin_directory }}"
+      system: true
+      shell: /bin/bash
+
+  - name: Add keeper_user to jellyfin group
+    ansible.builtin.user:
+      name: "{{ keeper_user }}"
+      groups: "{{ jellyfin_group }}"
+      append: true
+
+  - name: Create Jellyfin directories
+    ansible.builtin.file:
+      path: "{{ item }}"
+      owner: "{{ jellyfin_user }}"
+      group: "{{ jellyfin_group }}"
+      state: directory
+      mode: '0750'
+    loop:
+      - "{{ jellyfin_directory }}"
+      - "{{ jellyfin_config_dir }}"
+      - "{{ jellyfin_cache_dir }}"
+
+  - name: Check if Docker is installed
+    ansible.builtin.stat:
+      path: /var/run/docker.sock
+    register: docker_socket
+
+  - name: Deploy Docker Compose configuration
+    ansible.builtin.template:
+      src: docker-compose.yml.j2
+      dest: "{{ jellyfin_directory }}/docker-compose.yml"
+      owner: "{{ jellyfin_user }}"
+      group: "{{ jellyfin_group }}"
+      mode: '0644'
+    notify:
+      - Stop Jellyfin
+      - Pull Jellyfin image
+      - Start Jellyfin
+
+  - name: Create systemd service for Docker Compose
+    ansible.builtin.template:
+      src: jellyfin.service.j2
+      dest: /etc/systemd/system/jellyfin.service
+      mode: '0644'
+    notify:
+      - Reload systemd
+      - Enable Jellyfin
+      - Start Jellyfin
+
+  handlers:
+  - name: Reload systemd
+    ansible.builtin.systemd:
+      daemon_reload: true
+
+  - name: Stop Jellyfin
+    ansible.builtin.command:
+      cmd: "docker compose down"
+      chdir: "{{ jellyfin_directory }}"
+      become_user: "{{ jellyfin_user }}"
+      become: true
+
+  - name: Pull Jellyfin image
+    ansible.builtin.command:
+      cmd: "docker compose pull"
+      chdir: "{{ jellyfin_directory }}"
+      become_user: "{{ jellyfin_user }}"
+      become: true
+
+  - name: Start Jellyfin
+    ansible.builtin.command:
+      cmd: "docker compose up -d"
+      chdir: "{{ jellyfin_directory }}"
+      become_user: "{{ jellyfin_user }}"
+      become: true
+
+  - name: Enable Jellyfin
+    ansible.builtin.systemd:
+      name: jellyfin
+      enabled: true
+      state: started
+      daemon_reload: true