feat: Add official Lao (lo_LA) language support

[bounkirdni-2025]

I have completed the full Lao localization for 1Panel, including frontend UI, backend modules, and language registration. Total 5,500+ lines added. Please review and merge. Best regards, Bone NI

[wanghe-fit2cloud]

@bounkirdni-2025

Please refine this PR further based on the approach mentioned in this issue comment:
#13134 (comment)

[bounkirdni-2025]

Hi Wang He, I have updated the PR with backend i18n files (lo.yaml and i18n.go) as requested. Everything is now 100% complete. Ready for merge!

[lan-yonghui]

Hello @bounkirdni-2025,

I reviewed your PR and noticed that the language support files haven’t been updated completely.

You can refer to the following PRs as examples:

• Add Persian (fa) translations #13100 .
• ref: Improve support for Persian (fa) language #13128 .
• add some translate and update Persian #13132 .

Please update all relevant language files and make sure the corresponding translations are complete.

[lan-yonghui]

Hi @bounkirdni-2025,

Just a friendly follow-up on this. Could you please take a look when you have a chance?

The PR still needs the remaining language files to be updated. Please refer to the examples above and complete the corresponding translations.

Thank you!