ci(lint): enforce var-naming[no-role-prefix] and production profile

[sbaerlocher]

Summary

• Remove var-naming[no-role-prefix] from the skip_list and add profile: production plus strict: true to .ansible-lint.
• The repository already satisfies the rule, so this locks in the current state rather than fixing a defect. All role registers pass because the rule strips a leading underscore before comparing the prefix, and molecule verify.yml registers sit at play level where the sub-rule cannot apply.
• No register renames were needed; the change is limited to the lint configuration.

Test plan

• Baseline run before the change: 0 failure(s), 0 warning(s) on 121 files
• Positive control: an invalid register name triggers var-naming[pattern]
• Positive control: an unprefixed register in a role triggers var-naming[no-role-prefix] once the skip entry is removed, and passes silently while it is present
• Run with the target config: Passed: 0 failure(s), 0 warning(s) on 121 files. Profile 'production' was required, and it passed.
• yamllint clean on the changed file
• CI green

[claude]

The lint-config change is correct and safe to merge.

• Removing var-naming[no-role-prefix] from skip_list is backed by the code: all role-scoped registers and set_fact names are properly prefixed (_tailscale_*, _alloy_*, alloy_ready, do_config_backups, …), the unprefixed vars: blocks (packages_keys, packages_list, …) all attach to ansible.builtin.include_role tasks (excluded from the no-role-prefix check), and molecule verify.yml registers live in playbooks rather than role task files.
• profile: production + strict: true is a reasonable CI hardening.

Left one non-blocking nit: under strict: true, warnings fail CI, so the warn_list entries effectively behave like a fail_list. Worth a look but not a blocker.

[claude]

All raised issues have been addressed. No new issues in the delta.

[sbaerlocher]

Removed the warn_list in the same PR: under strict: true those two entries would act as a fail_list rather than as warnings. Both rules are meant to be enforced.

[claude]

All raised issues have been addressed.