feat: multi-language support (pt/es) + internationalize remaining strings

[opastorello]

Summary

Ship full multi-language support: add pt/es catalogs, internationalize the remaining hardcoded strings, and fix several i18n leaks (some visible even in English). The locale stays a single global value driven by NEXT_PUBLIC_APP_LOCALE; English remains the default and fallback.

What changed

• New catalogs: messages/pt.json (pt-BR) and messages/es.json (es-419), key-for-key identical to en.json (1683 leaf keys each; ICU/interpolation arguments preserved).
• ~250 hardcoded strings internationalized across ~30 files: Notifications, AI agent (page + Playground + Usage), Signup, Forgot password, Join/invite, Flows header, interactive message builder/preview, flow & automation template galleries, theme picker, and scattered toasts/placeholders/aria-labels.
• Bug fixes (raw keys shown even in English): missing Settings.sections.quick-replies; Overview role chip scope 'roles' -> 'Settings.roles'; scopesHint <code className> -> attribute-less <code>.
• Base UI Select triggers: 14 bare <SelectValue /> now render the selected option's translated label instead of the raw enum value.
• API scope descriptions moved to Settings.apiKeys.scopeDesc.*.

Data files (flow/automation templates, themes) keep English name/description as seed fallback; galleries resolve display copy via useTranslations keyed by each item's stable id.

Test plan

• npm run typecheck clean.
• npm run lint — 0 errors.
• npm run build succeeds.
• en/pt/es catalogs verified key-for-key identical; ICU argument parity checked per-string (0 mismatches); all useTranslations scopes resolve to a catalog namespace (guards against raw-key leaks).
• Deployed with NEXT_PUBLIC_APP_LOCALE=pt and spot-checked the converted screens.

Related

Closes #375. Also resolves #173 (make UI text translatable without fork conflicts).

[ivanmercedes]

Great work on this!

One small note: this PR also appears to resolve issue #173, so it might be worth adding Closes #173

[opastorello]

Thanks @ivanmercedes! Good catch — updated the description to reference #173. This PR follows exactly that shape: English stays the default and fallback, and adding a locale is just one new messages/<locale>.json file, so forks can translate without fighting merge conflicts.

[ArnasDon]

Reviewed the branch locally — key parity (1683 keys × en/es/pt), ICU argument parity, typecheck, and lint (0 errors) all check out, and request.ts loads the new catalogs correctly. A couple of small things worth improving:

1. Missing t in some useCallback deps. A few converted callbacks now call t() but don't list it in their dependency array, unlike the other files in this PR — it adds new react-hooks/exhaustive-deps warnings:

• members-tab.tsx (load, ~L177)
• whatsapp-config.tsx (~L166)
• quick-replies-manager.tsx (save L113, remove L125)

Harmless with a fixed global locale, but worth aligning for consistency (or intentionally leaving them all out).

2. Two pre-existing raw-key leaks not covered (optional, since this PR is cleaning up i18n leaks anyway):

• automation-builder.tsx:1157 — t("delete", { defaultValue: "Delete" })
• contact-detail-view.tsx:471 — t("tabs.tags", { fallback: "Tags" })

next-intl ignores defaultValue/fallback, and neither key exists, so both render the raw key path. Adding Automations.builder.delete and Contacts.detailView.tabs.tags (× 3 locales) would fix them.

Neither blocks merge — otherwise LGTM.

[opastorello]

Thanks for the thorough review @ArnasDon! Both points addressed in d539518:

1. useCallback deps — added t to the dependency arrays in members-tab.tsx, whatsapp-config.tsx, and quick-replies-manager.tsx (both save and remove), matching the convention used elsewhere in the PR. The three exhaustive-deps warnings are gone.
2. Raw-key leaks — added Automations.builder.delete and Contacts.detailView.tabs.tags to all three catalogs (en/pt/es, now 1685 keys each, still in full parity) and dropped the ignored defaultValue/fallback options from the call sites.

typecheck and lint (0 errors) still clean.