feat(upgrade): MCOL-6028 upgrade MVP with repo-managed flow, prechecks, and other enhancements

Implements the initial upgrade capability across CMAPI and the CLI, including
repository setup, package operations, environment prechecks, and coordinated
cluster steps with progress reporting.

Details:
- CMAPI upgrade manager:
  - Add `cmapi/cmapi_server/managers/upgrade/` modules:
    - `repo.py`, `packages.py`, `preinstall.py`, `upgrade.py`, `utils.py` and `__init__.py`
  - Extend endpoints and routing to expose upgrade operations and status:
    - `cmapi_server/controllers/{endpoints.py, dispatcher.py, api_clients.py}`
    - `cmapi_server/managers/{application.py, process.py}`
    - Add improved constants and helpers for upgrade flow
- Backup/restore and safety:
  - Add `cmapi_server/managers/backup_restore.py`
  - Fix pre-upgrade backup regressions (due to `mcs_backup_manager.sh 3.17 changes`)
  - Improve cluster version validation; add `ignore_missmatch` override
- CLI enhancements:
  - Progress UI and richer feedback (`mcs_cluster_tool/tools_commands.py`, `README.md`, `mcs.1`)
  - Add steps to start MDB and start MCS during/after upgrade
  - Improved error surfacing for version validation
- Platform and packaging:
  - Ubuntu and Rocky Linux support
  - RHEL/DNF dry-run support
  - Distro detection and platform-dependent logic hardened
  - Logging improvements
- Updater service:
  - Add `cmapi/updater/cmapi_updater.service.template` and `cmapi_updater.sh` to make CMAPI update itself
- Docs:
  - Update mcs cli README and mcs.1 man file
  - Add `cmapi/updater/README.md`

cmapi/cmapi_server/test/config_apply_example.py

@@ -4,7 +4,7 @@ import configparser
 from pathlib import Path
 from datetime import datetime
 
-from cmapi_server.controllers.dispatcher import _version
+from cmapi_server.constants import _version
 
 config_filename = './cmapi_server/cmapi_server.conf'