feat(i18n): Localization pipeline (UI + backend payloads + CI gates)

.github/plan/i18n-nontranslated-allowlist.md

@@ -0,0 +1,10 @@
+# i18n Non-Translated Allowlist (Technical)
+
+This list documents string categories that may remain untranslated for technical reasons.
+
+- File system paths and filenames.
+- External service URLs and domains.
+- Log channel names and event IDs.
+- Raw technical tokens (extensions, MIME types, enum IDs).
+- Version tags and semantic versions.
+- Vendor/product proper names (unless a localized marketing label exists).

.github/plan/i18n-strict-implementation-plan.md

@@ -0,0 +1,176 @@
+# Strict i18n rollout plan - RapidRAW
+
+## 1) Objective
+
+Deliver a fully enforced, CI-gated internationalization foundation for the React UI and the Tauri backend-to-frontend messaging so every visible string flows through localization keys.
+
+Expected outcomes:
+
+- Every UX string (buttons, tooltips, placeholders, modals, toasts, state text) relies on translation keys.
+- Backend emits send only translation key identifiers and optional interpolation params.
+- The localization pipeline includes ICU formatting from day one to handle plurals/genders/messages.
+- CI rejects any regression related to missing/empty placeholders or backend hardcoded text.
+
+## 2) Technical decisions
+
+- The frontend (React + i18next) is the single source of translated content.
+- The backend emits translation keys (`{ key, params }`) instead of final localized text.
+- English (`en`) remains the reference locale.
+- Priority locales are French (`fr`), Spanish (`es`), then English (`en`) (for fallback).
+- ICU (`i18next-icu`) loads by default to cover pluralization/gender needs out of the box.
+- The runtime fallback is `en`, but the CI tracks completion for `fr`/`es` primarily.
+- Any failure of the localization checks blocks merges.
+- Orphan keys (defined in `fr`/`es` but missing from `en`) generate warnings, not failure.
+
+## 3) Scope v1
+
+- Desktop app (React + Tauri channels).
+- Core UI: Library, side panels, all modals (panorama, HDR, denoise, settings, metadata, AI tools), toasts, tooltips, and status labels.
+- Critical backend flows: denoise progress, panorama progress/warnings/errors, HDR progress/errors, AI model downloads, export/import status.
+
+## 4) Target architecture
+
+- Frontend libs: `i18next`, `react-i18next`, `i18next-http-backend` (optional for lazy loading), `i18next-icu` (required from day one).
+- Locale files: `src/i18n/locales/fr/*.json`, `src/i18n/locales/es/*.json`, `src/i18n/locales/en/*.json` following `namespace.section.action` naming.
+- Infrastructure: `src/i18n/i18n.ts`, `scripts/i18n/check-translations.mjs`, `scripts/i18n/check-hardcoded-ui.mjs`, `scripts/i18n/check-backend-emits.mjs`.
+
+## 5) Quality rules enforced by CI
+
+- `R1`: No missing key in `fr` or `es` for any `en` key (blocks merge).
+- `R2`: No translation value may be empty (`""`, whitespace, `null`) in `fr` or `es`.
+- `R3`: Placeholder sets must match exactly between `en` and the target locale.
+- `R4`: No hardcoded text in React components beyond an allowlisted set (paths, technical tokens).
+- `R5`: Backend emits may not include raw text strings for localized channels.
+- `R6`: Locale selection persists in AppSettings (TypeScript + Rust) and survives restart.
+- `R7`: Orphan keys (present in `fr`/`es` but absent from `en`) surface as warnings only.
+- `R8`: ICU formatting support is enabled by default to cover plural/gender needs.
+
+## 6) Implementation phases and gates
+
+### Phase 0 – Scoping (blocking prerequisite)
+
+- Confirm release locales (fr, es, en) and list future targets.
+- Define key naming conventions (`namespace.section.action` or similar).
+- Set fallback policy (default `en`, explicit fail on fallback usage in CI).
+- Document the allowlist of strings that remain untranslated for technical reasons.
+
+Deliverables:
+
+- Documented locale priority list and naming convention.
+- Allowlist of non-translated strings.
+
+Gate: Phase 1 cannot start without locale list approval.
+
+### Phase 1 – Frontend i18n infrastructure
+
+- Initialize `i18next` with `i18next-icu` support and wrap `<App />` in `I18nextProvider`.
+- Create namespaces (`common`, `library`, `settings`, `modals`, `backend`, `errors`).
+- Persist locale in `AppSettings` (TS + Rust) and expose a UI switch honoring `fr`/`es`/`en` priority.
+- On startup, load persisted locale; fall back to `fr` if available, then `es`, then `en`.
+
+Deliverables:
+
+- Language switcher that respects priority locales.
+- Locale persistence surviving relaunch.
+
+Gate: manual verification of language switch + restart.
+
+### Phase 2 – UI translation migration
+
+- Move UI text into translation JSON (start with `MainLibrary`, `SettingsPanel`, modals, key components noted in `.github/plan`).
+- Replace strings with `t('namespace.key')` calls and ensure placeholders follow ICU syntax.
+- Capture tooltips, aria-labels, buttons, input placeholders.
+- Maintain allowlist for untouched technical strings.
+
+Deliverables:
+
+- All components in scope using translation keys instead of raw text.
+
+Gate: `scripts/i18n/check-hardcoded-ui.mjs` passes for in-scope files.
+
+### Phase 3 – Backend message localization
+
+- Change backend emits (panorama, denoise, hdr, AI download, exports) to send `{ key, params }` payloads instead of raw strings.
+- Document the key naming under `backend.*` namespace.
+- Update React listeners to call `t(payload.key, payload.params)` before updating UI state.
+
+Deliverables:
+
+- No backend-localized strings remain.
+
+Gate: `scripts/i18n/check-backend-emits.mjs` reports zero raw emits.
+
+### Phase 4 – CI automation
+
+- Add npm scripts: `i18n:check:translations`, `i18n:check:hardcoded`, `i18n:check:backend`, `i18n:ci` (combines all).
+- `i18n:check:translations` enforces missing/empty/placeholder rules for FR/ES/EN and reports warnings for orphans.
+- Integrate `i18n:ci` into the main CI pipeline.
+
+Deliverables:
+
+- CI job failing on any rule violation.
+
+Gate: proof-of-failure PR (intentional translation violation) causes CI to fail.
+
+### Phase 5 – Release stabilization
+
+- Run QA per locale (FR, ES, EN) across OSs (Linux/macOS/Windows) and themes (light/dark).
+- Verify modal, tooltip, error coverage, pluralization, and UI fit.
+- Record any orphan warnings for triage (non-blocking) with tickets.
+
+Deliverables:
+
+- QA checklist signed off for priority locales.
+
+Gate: QA sign-off + CI green.
+
+## 7) Translation completeness methodology
+
+- Source of truth: `en` locale files.
+- For each `en` key: verify target locale has a non-empty value of the same type and matching placeholder set (`{{var}}`).
+- Track missing/empty/placeholder mismatch/type mismatch counts.
+- Completion score = `(total - invalid) / total * 100`.
+- Release requirement: `100%` for FR/ES.
+- Dev requirement: `>=98%` with documented allowlist exceptions.
+- Empty/whitespace/`TODO`/`TBD` values fail.
+- Placeholder set order is irrelevant but all tokens must match.
+- Orphan keys cause warnings, not failure; they generate tickets for cleanup.
+
+## 8) Testing and validation
+
+### Scripted checks (CI)
+
+- `i18n:check:translations`: guard missing/empty/placeholder issues for FR/ES; warns on orphans.
+- `i18n:check:hardcoded`: scans React components for literal text in the scoped directories.
+- `i18n:check:backend`: ensures backend emits never carry raw strings.
+- `i18n:ci`: aggregates the above and runs in CI.
+
+### Integration tests
+
+- Backend listeners confirm they translate payloads in the active locale.
+- Language switching updates live UI texts and modal progress messages.
+- Locale persistence test: change locale, restart, observe same locale.
+
+### Manual QA
+
+- Walk through Library, Settings, modal flows in FR/ES/EN.
+- Ensure progress messages (denoise/panorama/hdr/import) show localized text.
+- Verify tooltip/placeholder coverage and layout for longer translations.
+- Lead special focus on pluralized messages (via ICU).
+- Document orphan warnings for follow-up cleanup.
+
+## 9) Definition of done
+
+- All visible strings use translation keys or documented allowlist.
+- Backend emits supply keys + params only.
+- Locale persistence implemented (TS + Rust) with priority `fr`, `es`, fallback `en`.
+- CI runs `i18n:ci` (includes ICU-aware checks) and blocks failures.
+- Release locale completion is 100%; orphan warnings logged for review.
+- Plan documents updated accordingly for future work (implementation awaited).
+
+## 10) Assumptions / clarifications
+
+- Locale priority: `fr` > `es` > `en`; release gating focuses on FR/ES, EN as fallback.
+- ICU integration is required immediately to handle pluralization/gender differences.
+- Orphan keys are warnings to be tracked elsewhere, not CI blockers.
+- This plan documents the decisions needed before any implementation starts (all work deferred).

.github/workflows/build.yml

@@ -82,6 +82,9 @@ jobs:
       - name: Install frontend dependencies
         run: npm install
 
+      - name: Run i18n checks
+        run: npm run i18n:ci
+
       - name: rustup install target
         if: ${{ inputs.target != '' }}
         run: rustup target add ${{ inputs.target }}