Retire kosync and dir2opds now that Kavita handles both

Kavita's KOReader sync API and OPDS feed replace them, and both readers
(Kindle KOReader, Xteink X4) now point at books.thesatelliteoflove.com.
Drops their stacks, the sync. and opds. routes and DNS records, and the
htpasswd tasks that only existed for dir2opds basic auth.

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

roles/docker/tasks/infrastructure/caddy.yml

@@ -5,41 +5,6 @@
   loop:
     - /opt/stacks/caddy
 
-- name: Install apache2-utils for htpasswd
-  ansible.builtin.apt:
-    name: apache2-utils
-    state: present
-    update_cache: true
-    cache_valid_time: 3600
-  become: true
-  when: vault_dir2opds is defined
-
-# bcrypt uses a random salt, so a fresh hash would change the Caddyfile (and
-# restart Caddy) on every run. Reuse the deployed hash while it still matches
-# the vault password; only make a new one when it doesn't.
-- name: Get bcrypt hash for dir2opds basic auth
-  ansible.builtin.shell: |
-    set -eu
-    cur=$(awk -v u="$AUTH_USER" '/basic_?auth/ {b=1} b && $1 == u {print $2; exit}' \
-          /opt/stacks/caddy/Caddyfile 2>/dev/null || true)
-    if [ -n "$cur" ]; then
-      tmp=$(mktemp); trap 'rm -f "$tmp"' EXIT
-      printf '%s:%s\n' "$AUTH_USER" "$cur" > "$tmp"
-      if htpasswd -vb "$tmp" "$AUTH_USER" "$AUTH_PASS" >/dev/null 2>&1; then
-        echo "$AUTH_USER $cur"
-        exit 0
-      fi
-    fi
-    htpasswd -bnB "$AUTH_USER" "$AUTH_PASS" | awk -F: 'NF {print $1, $2}'
-  environment:
-    AUTH_USER: "{{ vault_dir2opds.basic_auth_user }}"
-    AUTH_PASS: "{{ vault_dir2opds.basic_auth_password }}"
-  register: dir2opds_basic_auth_hash_result
-  changed_when: false
-  check_mode: false
-  no_log: true
-  when: vault_dir2opds is defined
-
 - name: template Caddyfile
   ansible.builtin.template:
     src: Caddyfile.j2