Add RU/KZ/ENG, dark theme and smooth 3D navigation

[zardol]

Changes

Adds saved RU / KZ / ENG interface languages and a green dark theme across all six workspaces. Theme and language changes preserve the active shift, plan edits and selected vehicle. Includes subtle page/control transitions and reduced-motion support.

Fixes the timer information button with a viewport-contained, keyboard-accessible popover. Clarifies AI hourly good-output capacity and replaces the active-plan badge with a source note explaining the 700 unallocated vehicles.

The 3D camera now preserves manual framing when resized or hidden, smoothly changes requested views, stops following a vehicle on manual input, bounds panning and ignores selection clicks after dragging.

Validation

• Full npm run check: TypeScript, 211 tests, production frontend/server and GitHub Pages builds.
• DOM interaction tests cover preferences, state preservation, timer help and the AI access-code prompt without paid requests.
• Camera tests cover portrait/wide framing, resize/hide/show, motion interruption and vehicle tracking.
• Translation coverage and placeholder consistency checks cover the complete UI catalogue.

The desktop browser automation runtime is unavailable, so a rendered browser walkthrough was not performed. Imported labels and free-form OpenAI reports retain their original language. The AI server and simulation model are unchanged.