* Enable reserved variable name checks and fix violations

Updated .ansible-lint configuration to skip only var-naming[pattern]
and var-naming[no-role-prefix] instead of skipping the entire var-naming rule.
This enables the check for reserved variable names.

Renamed variables that used reserved names to avoid conflicts.
Updated all references in tasks, variables, and templates.

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

* Rename namespace variable inside tasks instead of deleting it

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

* Change hosts variable to vm_hosts

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

* Use k8s_namespace instead of dashboard_namespace in dashboard.yml.j2 template

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

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Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

The option ara_default was still present in ansible.cfg under callbacks_enabled.
This is a leftover from commit b9e9364c ("Remove ara support in CI") and should
have been removed together with the rest of the ara integration.

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

Signed-off-by: wangsifei99 <wangsifei@kylinos.cn>

Signed-off-by: Ali Afsharzadeh <afsharzadeh8@gmail.com>

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Signed-off-by: Hyeonki Hong <hhk7734@gmail.com>