uptime-kuma: add uptime_kuma_enabled flag and make monitoring blocks inert

Removing the credentials would otherwise break these playbooks mid-deploy: they
template uptime_kuma_password with no assert to stop them first. 100 tasks are
now guarded by uptime_kuma_enabled (false), so deployments run normally and the
monitoring sections skip. A further 28 tasks were already self-guarding on
monitor_setup/push_url being defined; verified that a skipped task's registered
variable makes those skip cleanly rather than error.

The blocks are kept on purpose — the health-check logic is the durable part and
should be rewired to whatever replaces Uptime Kuma.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

ansible/services/mempool/deploy_mempool_playbook.yml

@@ -226,7 +226,18 @@
       delay: 5
       ignore_errors: yes
 
+    # ═════════════════════════════════════════════════════════════════════════
+    # DEPRECATED — Uptime Kuma was decommissioned on 2026-09-11.
+    #
+    # Every task below is inert: uptime_kuma_enabled is false in
+    # group_vars/all/main.yml, so they all skip and the deployment above still
+    # runs normally. Kept because the health-check logic is the durable part —
+    # when a replacement exists, rewire the push transport and flip the flag.
+    #
+    # What was being monitored: archive/uptime_kuma/MONITORS.md
+    # ═════════════════════════════════════════════════════════════════════════
     - name: Display deployment status
+      when: uptime_kuma_enabled | default(false)
       debug:
         msg:
           - "Mempool deployment complete!"
@@ -239,6 +250,7 @@
     # Health Check Scripts for Uptime Kuma Push Monitors
     # ===========================================
     - name: Create Mempool MariaDB health check script
+      when: uptime_kuma_enabled | default(false)
       copy:
         dest: /usr/local/bin/mempool-mariadb-healthcheck-push.sh
         content: |
@@ -273,6 +285,7 @@
         mode: '0755'
 
     - name: Create Mempool backend health check script
+      when: uptime_kuma_enabled | default(false)
       copy:
         dest: /usr/local/bin/mempool-backend-healthcheck-push.sh
         content: |
@@ -307,6 +320,7 @@
         mode: '0755'
 
     - name: Create Mempool frontend health check script
+      when: uptime_kuma_enabled | default(false)
       copy:
         dest: /usr/local/bin/mempool-frontend-healthcheck-push.sh
         content: |
@@ -396,6 +410,7 @@
         daemon_reload: yes
 
     - name: Enable and start health check timers
+      when: uptime_kuma_enabled | default(false)
       systemd:
         name: "mempool-{{ item }}-healthcheck.timer"
         enabled: yes
@@ -409,6 +424,7 @@
     # Uptime Kuma Push Monitor Setup
     # ===========================================
     - name: Create Uptime Kuma push monitor setup script for Mempool
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       copy:
@@ -492,6 +508,7 @@
         mode: '0755'
 
     - name: Create temporary config for monitor setup
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       copy:
@@ -507,6 +524,7 @@
         mode: '0644'
 
     - name: Run Uptime Kuma push monitor setup
+      when: uptime_kuma_enabled | default(false)
       command: python3 /tmp/setup_mempool_monitors.py
       delegate_to: localhost
       become: no
@@ -520,6 +538,7 @@
       when: monitor_setup.stdout is defined
 
     - name: Read push URLs from file
+      when: uptime_kuma_enabled | default(false)
       slurp:
         src: /tmp/mempool_push_urls.yml
       delegate_to: localhost
@@ -573,6 +592,7 @@
       when: push_urls is defined
 
     - name: Clean up temporary files
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       file:
@@ -637,6 +657,7 @@
         state: reloaded
 
     - name: Display Mempool URL
+      when: uptime_kuma_enabled | default(false)
       debug:
         msg: "Mempool is now available at https://{{ mempool_domain }}"
 
@@ -644,6 +665,7 @@
     # Uptime Kuma HTTP Monitor for Public Endpoint
     # ===========================================
     - name: Create Uptime Kuma HTTP monitor setup script for Mempool
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       copy:
@@ -714,6 +736,7 @@
         mode: '0755'
 
     - name: Create temporary config for HTTP monitor setup
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       copy:
@@ -727,6 +750,7 @@
         mode: '0644'
 
     - name: Run Uptime Kuma HTTP monitor setup
+      when: uptime_kuma_enabled | default(false)
       command: python3 /tmp/setup_mempool_http_monitor.py
       delegate_to: localhost
       become: no
@@ -740,6 +764,7 @@
       when: http_monitor_setup.stdout is defined
 
     - name: Clean up HTTP monitor temporary files
+      when: uptime_kuma_enabled | default(false)
       delegate_to: localhost
       become: no
       file: