Translation update proposals

[Blackspirits]

This pull request centralizes the Vietnamese and Serbian Latin translation
reviews previously proposed separately, while preserving the changes already
present on the isl-update-proposals branch.

It also includes two isolated Hebrew placeholder fixes.

Vietnamese

• Fully reviewed against the current Default.isl
• Reconciled with the earlier Vietnamese proposal and the existing maintainer changes
• Corrected translation accuracy, terminology, grammar, source fidelity, and UI consistency
• Restored omitted Setup actors and mandatory meanings such as must
• Preserved literal technical paths such as C:\App and \\server\share
• Passed both the ISL-specific automated QA and an independent UI-localization QA
• 293 matching entries and no confirmed technical issues

Native Vietnamese confirmation is still recommended.

Serbian Latin

• Fully reviewed against the current Default.isl
• Reconciled with the earlier Serbian Latin proposal
• Corrected grammar, punctuation, terminology, source fidelity, and UI consistency
• Restored omitted meanings such as all, now, later, automatically, and successfully
• Preserved technical terms such as Power Users and RestartReplace
• Corrected registry terminology, shortcuts, file extensions, restart messages, uninstall logs, and related strings
• Passed both the ISL-specific automated QA and an independent UI-localization QA
• 293 matching entries and no confirmed technical issues

Native Serbian confirmation is still recommended.

Hebrew

Only two targeted placeholder defects were changed:

• ErrorProgress: second %1 corrected to %2
• ErrorFileSize: second %1 corrected to %2

Other pre-existing Hebrew translation issues are intentionally outside the
scope of this pull request.

Validation

• UTF-8 without BOM preserved
• CRLF line endings preserved
• No missing or additional IDs in Vietnamese or Serbian Latin
• No placeholder mismatches in Vietnamese or Serbian Latin
• git diff --check passes
• Only the three intended translation files are included
• No local reports, QA tools, skills, or private files are included

This pull request supersedes the separate Vietnamese and Serbian Latin pull
requests.

[martijnlaan]

Cherry picked your Hebrew changes in eafc69c