## Summary
Replaces the AWS Translate i18n pipeline with a DeepSeek (LLM) backend,
standardizes locale files to BCP-47 naming with an `en-US` base, adds
new languages, and backfills **every locale to 100%**.
## What changed
### Translation engine (DeepSeek)
- Swap AWS Translate → DeepSeek via its OpenAI-compatible API
(`scripts/translations/`). Auth via the `DEEPSEEK_API_KEY` secret;
per-request 60s timeout.
- **Batched** translation (50/call) with **per-string validation**:
interpolation placeholders (`{count}`, `%s`, `@:key`), vue-i18n
**pluralization pipes** (`{n} Day \| {n} Days`), and literal escapes
(`{'@'}`, `{'{'}`, `{'\|'}`) are preserved or the string is rejected and
retried.
- Robust recovery: index-aligned batches, split-on-mismatch to isolate a
single bad string, temperature-perturbed retries, and rejection of
empty/whitespace output (never blanks a label). Removed the old
`TRANSLATION_MAX_KEYS` safety cap.
### Locale naming + base language
- All 15 locale files renamed to **BCP-47 hyphen** form (`en-US.json`,
`zh-CN.json`, `zh-TW.json`, `fr-FR.json`, …) — matching
`navigator.language` / `Intl` / HTML `lang`.
- **English base switched `en-gb` → `en-us`** (app code,
`fallbackLocale`, BCP-47 map, selector, defaults). British-Pound
currency and date-formatting `en-GB` usages left untouched. Existing
`en-gb` cookies fall back cleanly to English — no migration needed.
### New languages
- **Russian (`ru`), Polish (`pl`), Vietnamese (`vi`)** — fully generated
and wired into `localeFileMap`, `APP_LOCALE_TO_BCP47`, and the language
selector.
- **Traditional Chinese (`zh-TW`)** now maintained by the translator
alongside Simplified (`zh-CN`).
- RTL languages (`ar`, `fa`) intentionally **deferred** until the app
has `dir="rtl"` support.
### Full backfill (one-time)
- Every pre-existing locale filled from ~5.9k up to the full **8,269
keys** (~26.9k strings). `.translation_state.json` rebuilt complete, so
future runs are incremental.
### Nav i18n bug fix
- The **Dashboards** and **Data** nav group labels were hardcoded
English (bypassing i18n) and stayed English in every locale. Now
resolved via `t()` (`menu.dashboard`, new `menu.data`), localized and
re-resolving on language change.
## Verification
- Full web unit suite: **39,035 passed / 414 skipped / 0 failed** (1,167
files).
- `type-check` clean (0 TS errors).
- Locale registry sync spec green; all 15 files = 8,269 leaves.
- Translation engine verified live against `deepseek-v4-flash`.
## Notes
- Since all locales are now 100%, the post-merge `update-translations`
workflow will find nothing pending (no follow-up translation PR).
- `ar`/`fa` to be added with RTL support in a follow-up.
Bhargavandgithub-actions[bot]
Abhay Padamaniandgithub-actions[bot]
ktx-vaidehiandKirtan Thakkar
Prabhat Sharma
