feat: migrate freecad-mcp to GitHub fork install and refactor deployments

- Switch freecad-mcp installation from PyPI to Heluca GitHub fork,
  using a configurable git ref (freecad_mcp_git_ref) instead of
  pinned PyPI version
- Retarget freecad-mcp deployment from Caliban to Larissa, update
  port from 22032 to 22063, and change service user to freecad-mcp
- Add git to apt dependencies for pip git+https installs
- Make deployment summary use inventory_hostname instead of hardcoded host
- Refactor kernos deploy to target all ubuntu hosts with service-based
  filtering via `services` host_var, replacing static host group

ansible/kernos/deploy.yml

@@ -1,10 +1,19 @@
 ---
 - name: Deploy Kernos MCP Shell Server
-  hosts: kernos
+  hosts: ubuntu
   vars:
-    ansible_common_remote_group: "{{kernos_group}}"
+    ansible_common_remote_group: "{{kernos_group | default([]) }}"
     allow_world_readable_tmpfiles: true
+
   tasks:
+  - name: Check if host has kernos service
+    ansible.builtin.set_fact:
+      has_kernos_service: "{{ 'kernos' in services | default([]) }}"
+
+  - name: Skip hosts without kernos service
+    ansible.builtin.meta: end_host
+    when: not has_kernos_service
+
   - name: Create Kernos group
     become: true
     ansible.builtin.group: