feat(desktop): add 11 new languages — hybrid JSON + TypeScript i18n system

[hashbender]

What

Adds 11 new Desktop UI locales and a hybrid JSON+TypeScript i18n system that combines the best of both approaches.

New locales (11 + 4 existing = 15 total):
ko (한국어), de (Deutsch), es (Español), fr (Français), pt-BR (Português Brasil), ar (العربية), hi (हिन्दी), th (ภาษาไทย), vi (Tiếng Việt), it (Italiano), ru (Русский)

Architecture — best of both worlds

locales/*.json              <- Canonical translation source (flat keys, easy for translators)
       |
       v
scripts/sync-locales.py     <- Validates -> generates defineLocale() .ts files
       |
       v
i18n/{code}.ts              <- Upstream type-safe framework (runtime, context, types)
       |
       v
i18n/types.ts / catalog.ts / languages.ts -> All 15 locales registered

JSON files (locales/*.json):

• Flat key-value pairs, ~850 Desktop UI strings each
• Translators only need to edit JSON - no TypeScript knowledge required
• Key parity test (locales.test.ts) catches regressions
• Drop a new {code}.json -> run sync-locales.py -> it works

TypeScript framework (i18n/*.ts):

• Uses upstream's existing infrastructure (feat(desktop): add i18n with Simplified Chinese (zh-Hans) support NousResearch/hermes-agent#38241): runtime.ts, context.tsx, define-locale.ts
• defineLocale() pattern: missing keys fall back to English automatically
• TypeScript validates all keys against the 1900-line Translations interface
• Upstream locales (en, ja, zh, zh-hant) preserved intact

Bridge script (scripts/sync-locales.py):

• Reads JSON -> validates keys against en.json -> generates defineLocale() .ts
• Updates catalog.ts, types.ts (Locale type), languages.ts automatically
• Run: python3 apps/desktop/scripts/sync-locales.py

Why this approach

Concern	JSON-only	TS-only (upstream)	Hybrid (this PR)
Translator DX	Drop JSON file	Must write TS	JSON still works
Type safety	None	Full type check	Full type check
Upstream compat	Custom framework	Uses merged infra	Uses merged infra
Add new language	Drop JSON	4 files to edit	Drop JSON + config
CI validation	Manual	tsc catches it	tsc + sync validate

Files changed

• 32 files, +24,000 / -804
• 11 new .ts locale catalogs
• 15 JSON locale files + test + TRANSLATING.md
• scripts/sync-locales.py - the bridge tool
• i18n/catalog.ts, types.ts, languages.ts - updated

Supersedes the earlier omnibus PR NousResearch#38846.
Closes the Russian Desktop locale gap noted in NousResearch#40347.

---

Mirror-of: NousResearch#56246
NousResearch#56246