[hzqst]

Fixes MetaHookSv/MetaHookSv#952.

When Career mission data is missing or corrupt, native CCareerMapFrame::OnThink creates a modal MessageBox with literal English title/body strings. Neither string starts with a localization token, so adding translations alone cannot translate this window. This path is separate from the plugin's profile-storage ShowError and the #951 confirmation-dialog fix.

Reuse the existing gamedata-resolved narrow MessageBox constructor and hook it only for czero, excluding Deleted Scenes. Replace the exact native title/body pair with two plugin tokens when each translation exists. The original constructor, error checks and modal lifecycle remain in use; missing translations retain the native English strings.

• Add VGUI2Extension_CareerDataErrorTitle and VGUI2Extension_CareerDataErrorText in UTF-16 LE BOM English and Simplified Chinese resources.
• Explicitly load plugin English first and the effective game language second during GameUI initialization, including -forcelang selection.
• Document translation entry points and record verification. No new gamedata records or native object-layout assumptions are needed.

Validation:

• MSVC x86 Release build, pinned format-check (66 files), all 8 existing CTests, staged install, and git diff --check passed.
• Live czero build 10210 at 1280x720: Simplified Chinese title/body, English title/body, and native-English fallback in a fresh Simplified Chinese process with both plugin language files absent. OK returned to profile selection.
• Runtime used a temporary mission pack with empty Maps to reach the same native no-triplet error branch. This was not a direct deleted-Normal.vdf test: missing per-pack files can fall back to global CareerGame<difficulty>.vdf. The checksum-failure branch and other engine builds were not separately exercised.
• All task-owned game processes exited cleanly; the temporary pack/profile was moved out and all 21 backed-up game files were restored and SHA256-verified.

Static diagnosis: MetaHookSv/MetaHookSv#952 (comment)