i18n(pt): complete and ship Brazilian Portuguese

- Translate the remaining 1,868 strings (pt-BR, as in #909) and review the
  contributor entries: HUD codes BRG/SPD/RANGE stay as in the other
  languages, sentence-case layer and scene names, Space key named as on the
  keyboard, short PREV/NEXT/ON/OFF chips, and the CLDR many form (exact
  millions take «de») on every plural.
- Register pt: any pt tag (pt-BR, pt-PT) maps to it; the picker shows
  «Português (Brasil)».
- Codes, units and product names identical to English go to
  same-as-english.json.
- docs/translations/pt.md: style, plurals, units and glossary.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/CURRENT-STATE.md

@@ -3733,7 +3733,7 @@ test:track` 43 tracking invariants · headless QA harnesses under
 
 ### Interface localization (October 2026)
 
-Shipped locales: **en** (source and fallback), **es**, **ru**, **zh-CN** and **zh-Hant**. The code lives in
+Shipped locales: **en** (source and fallback), **es**, **pt** (Brazilian Portuguese), **ru**, **zh-CN** and **zh-Hant**. The code lives in
 `src/i18n/`. How to mark UI text: [`docs/I18N.md`](./I18N.md); translator workflow:
 [`docs/TRANSLATORS.md`](./TRANSLATORS.md).
 
@@ -3744,7 +3744,7 @@ Shipped locales: **en** (source and fallback), **es**, **ru**, **zh-CN** and **z
   value). English has no catalog; every other locale is
   `src/i18n/locales/<code>.json`, and a missing entry falls back to English.
 - **Locale choice.** `?lang=` → stored choice (`gev:locale:v1`) →
-  `navigator.languages` → English. Chinese tags default to `zh-CN`; Traditional Chinese tags
+  `navigator.languages` → English. Any `pt` tag (`pt-BR`, `pt-PT`) selects `pt`. Chinese tags default to `zh-CN`; Traditional Chinese tags
   select `zh-Hant`. Explicit `Hans` selects `zh-CN` regardless of region. `?lang=` is not stored, and share links drop
   it, so a recipient keeps their own language. The globe picker in the
   bottom-right corner (`src/ui/localePicker.js`) stores the choice, drops

docs/TRANSLATORS.md

@@ -1,6 +1,6 @@
 # Translating God's Eye View
 
-Shipped languages: **English** (source and fallback), **Spanish** (`es`), **Russian** (`ru`), **Simplified Chinese** (`zh-CN`) and **Traditional Chinese** (`zh-Hant`).
+Shipped languages: **English** (source and fallback), **Spanish** (`es`), **Brazilian Portuguese** (`pt`), **Russian** (`ru`), **Simplified Chinese** (`zh-CN`) and **Traditional Chinese** (`zh-Hant`).
 
 ## How it works
 
@@ -63,4 +63,4 @@ These are contracts, not copy: layer ids and registry keys, status enums and oth
 
 ## Language notes
 
-Each language keeps its glossary, plural forms, units and style in its own file, `docs/translations/<code>.md`: [Spanish](./translations/es.md), [Russian](./translations/ru.md), [Simplified Chinese](./translations/zh-CN.md), [Traditional Chinese](./translations/zh-Hant.md). Read it before translating, and add a term there when you settle on one.
+Each language keeps its glossary, plural forms, units and style in its own file, `docs/translations/<code>.md`: [Spanish](./translations/es.md), [Brazilian Portuguese](./translations/pt.md), [Russian](./translations/ru.md), [Simplified Chinese](./translations/zh-CN.md), [Traditional Chinese](./translations/zh-Hant.md). Read it before translating, and add a term there when you settle on one.

docs/translations/pt.md

@@ -0,0 +1,81 @@
+# Brazilian Portuguese (`pt`)
+
+Catalog: `src/i18n/locales/pt.json`. General rules: [TRANSLATORS.md](../TRANSLATORS.md).
+
+Translation source: abiyeenzo (#909).
+
+## Style
+
+- Brazilian Portuguese (pt-BR): câmera, tela, compartilhar, arquivo, baixar, ônibus, metrô. Every `pt` tag, `pt-PT` included, gets this catalog, so avoid slang and regionalisms.
+- Address the user with «você» imperatives: «Clique no mapa», «Ative o CCTV», «Tente novamente». Tooltips that name an action use the infinitive: «Expandir painel», «Redefinir a câmera».
+- Sentence case, not Title Case: "Live Flights" → «Voos ao vivo». UPPERCASE English stays UPPERCASE: «AO VIVO», «SEM DADOS».
+- Quotes inside Portuguese text are straight double quotes: «Excluir o plano "{shot}"?».
+- Short labels, chips and HUD readouts stay short. A standard abbreviation with a period beats a wrapped line: ANT., PRÓX., DESLIG., EXCL., INCL., ALT., VEL., câm.
+- The HUD codes HDG, BRG, CRS, FOV, DEST, SPD, RANGE, ALT, GS and TRK stay in English, as in cockpit avionics. Words used in a sentence are translated: heading → «rumo», range → «alcance».
+- Keyboard keys stay in English: Space, Esc, Enter, Tab, Shift, Backspace, H, 1–9 («Segure Space para falar»).
+- Common English tech words used in Brazil stay: feed, stream, snapshot, briefing, dock, layout, bloom, status, app, link, token.
+- Units: km, m, km/h, m/s, kt (knots), ft (feet), h, min, s; in UPPERCASE text KM, KM/S, KT, FT, MIN, H. "m" is always metres, so minutes are «min» («há 5 min»). MW stays MW. `°` and `%` stay. Decimal comma in written numbers («M4,4»).
+- "ago" goes before the time: «há {count} min». When a placeholder already holds a localized "ago" text (`{age}`, `{ago}`), do not add «há» again.
+- Money: «US$ {amount} mil / mi / bi» for thousands, millions and billions.
+- Compass points use Leste/Oeste: N, NNE, NE, ENE, L, ESE, SE, SSE, S, SSO, SO, OSO, O, ONO, NO, NNO; hemisphere letters N, S, L, O.
+
+## Plurals
+
+A `tn()` entry needs three forms. `Intl.PluralRules('pt')` follows Brazilian usage:
+
+| Form    | Counts                                 | Example            |
+| ------- | -------------------------------------- | ------------------ |
+| `one`   | 0, 1 and anything below 2: 0, 1, 1.5   | 0 câmera, 1 câmera |
+| `many`  | 1 000 000, 2 000 000… (exact millions) | 1000000 de câmeras |
+| `other` | everything else: 2–999 999, 2.5…       | 3 câmeras          |
+
+The `many` form is the `other` text with «de» after the number: «{count} de câmeras carregadas», «{count} DE CHAVES PENDENTES». A `one` form is also read for 0, so keep it natural with zero («0 arquivo selecionado» is standard Brazilian usage).
+
+## Glossary
+
+| English                                       | Português                                                    |
+| --------------------------------------------- | ------------------------------------------------------------ |
+| layer / data layer                            | camada / camada de dados                                     |
+| feed / source / data source                   | feed / fonte / fonte de dados                                |
+| LIVE (status) / live data                     | AO VIVO / dados ao vivo                                      |
+| SIMULATED                                     | SIMULADO                                                     |
+| stale / degraded / unavailable                | desatualizado / degradado / indisponível                     |
+| retry / retrying                              | nova tentativa / tentando de novo                            |
+| key (API key) / POWER UP / POWERED UP         | chave / ATIVAR / ATIVADO                                     |
+| Provider Settings                             | Configurações de provedores                                  |
+| ON / OFF (state chips)                        | ATIVO / INATIVO                                              |
+| enable / disable                              | ativar / desativar                                           |
+| globe / map / map source / map stack          | globo / mapa / fonte do mapa / pilha de mapas                |
+| basemap / tile                                | mapa base / bloco                                            |
+| aircraft, plane / flight / military flights   | aeronave, avião / voo / voos militares                       |
+| vessel, ship                                  | embarcação                                                   |
+| satellite / shell (Starlink) / DENSE          | satélite / camada orbital / DENSO                            |
+| launch (rocket) / launch site / space mission | lançamento / local de lançamento / missão espacial           |
+| ascent / replay / payload / stage             | subida / reprise / carga útil / estágio                      |
+| contact / tracking / track                    | contato / rastreamento / rastro                              |
+| installation / site                           | instalação / local                                           |
+| mapped / observed                             | mapeado / observado                                          |
+| camera / CCTV camera                          | câmera / câmera de CCTV                                      |
+| earthquake / active fire                      | terremoto / incêndio ativo                                   |
+| advisory (NHC/CPHC cyclone)                   | boletim                                                      |
+| radio station / broadcaster                   | estação de rádio / emissora                                  |
+| road / flow (traffic)                         | via / fluxo                                                  |
+| Street Level (layer)                          | Nível da rua                                                 |
+| scene / shot / scene recipe                   | cena / plano / receita de cena                               |
+| briefing / panel / dock                       | briefing / painel / dock                                     |
+| cockpit                                       | cabine                                                       |
+| preset / visual preset                        | predefinição / predefinição visual                           |
+| Scope (circular viewport mask) / keyhole      | mira / visor                                                 |
+| feather / fade                                | suavização / esmaecimento                                    |
+| detection overlay                             | sobreposição de detecção                                     |
+| pin (Draw tool) / box (Recent Imagery)        | marcador / área                                              |
+| Cyber (HUD layout, effect)                    | Ciber                                                        |
+| heading / course / altitude / ground speed    | rumo / curso / altitude / velocidade solo (VELOC. SOLO)      |
+| HDG / BRG / CRS / FOV / DEST / SPD / RANGE    | HDG / BRG / CRS / FOV / DEST / SPD / RANGE (unchanged)       |
+| PREV / NEXT                                   | ANT. / PRÓX.                                                 |
+| Previous / Next (button text)                 | Anterior / Próximo (Próxima)                                 |
+| L / R (relative bearing)                      | E / D                                                        |
+| SIG / NEWS / LOCAL (briefing tabs)            | SIG / NOTÍCIAS / LOCAL                                       |
+| PITCH / HGT (CCTV calibration chips)          | INCL. / ALT.                                                 |
+| NOT AN ALL-CLEAR                              | NÃO GARANTE SEGURANÇA                                        |
+| turn-by-turn: turn left / keep left / lane    | vire à esquerda / mantenha-se à esquerda / faixa da esquerda |