Translate the entire repo to English (UI strings, README, CI, comments)

Prep for public distribution. All user-facing strings, the README, the Gitea
workflow step names/comments and the keystore example are now English.
Follow-up i18n (string resources + locale files) is tracked in #5.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -1,110 +1,117 @@
 # PaperScan
 
-Een lokale, privacy-bewuste documentscanner voor Android. Scant papieren documenten
-met de camera, detecteert automatisch de randen, corrigeert het perspectief en bundelt
-meerdere pagina's in één PDF. Die PDF kun je delen via Android of rechtstreeks uploaden
-naar je zelf-gehoste **Paperless-ngx**.
+A local, privacy-conscious document scanner for Android. Scan paper documents with your
+camera, automatically detect the edges, correct the perspective, and bundle multiple pages
+into a single PDF. That PDF can be shared through Android or uploaded directly to your
+self-hosted **Paperless-ngx**.
 
-**Alles gebeurt op het toestel.** Camerabeelden, randdetectie (OpenCV) en PDF-creatie
-verlaten je telefoon niet. De enige netwerkverbinding is de optionele upload naar de
-Paperless-server die jij zelf configureert. Er is geen AI of cloud-verwerking.
+**Everything happens on the device.** Camera frames, edge detection (OpenCV) and PDF
+creation never leave your phone. The only network connection is the optional upload to the
+Paperless server you configure yourself. There is no AI or cloud processing.
 
-## Functies
+## Features
 
-- 📷 Camerapreview met multi-page vastleggen (pagina na pagina toevoegen)
-- ✂️ Automatische randdetectie + perspectiefcorrectie (OpenCV), met handmatige hoekcorrectie
-- 🎨 Filters per pagina: kleur, grijstinten, zwart-wit (documentmodus)
-- 🔄 Pagina's draaien, herordenen en verwijderen
-- 📄 Export naar multi-page PDF (A4 of originele grootte)
-- ☁️ Directe upload naar Paperless-ngx **of** delen via het Android-deelmenu
-- 🔐 API-token versleuteld opgeslagen (Android Keystore / EncryptedSharedPreferences)
+- 📷 Camera preview with multi-page capture (add pages one by one)
+- ✂️ Automatic edge detection + perspective correction (OpenCV), with manual corner adjustment
+- 🎨 Per-page filters: color, grayscale, black & white (document mode)
+- 🔄 Rotate, reorder and delete pages
+- 📄 Export to a multi-page PDF (A4 or original size)
+- ☁️ Direct upload to Paperless-ngx **or** share via the Android share sheet
+- 🔊 Capture feedback: shutter sound (only when the ringer isn't silenced) + a brief flash
+- 🔐 API token stored encrypted (Android Keystore / EncryptedSharedPreferences)
 
 ## Tech
 
 Kotlin · Jetpack Compose · CameraX · OpenCV (`org.opencv:opencv` via Maven) ·
 `PdfDocument` · OkHttp · DataStore. minSdk 26 (Android 8), target/compile SDK 35.
 
-## Lokaal bouwen
+## Building locally
 
-1. Open het project in **Android Studio** (Ladybug of nieuwer). Dit genereert automatisch
-   de Gradle wrapper (`gradlew` + `gradle-wrapper.jar`).
-2. Sluit een toestel aan of start een emulator en druk op **Run**.
+1. Open the project in **Android Studio** (Ladybug or newer). This automatically generates
+   the Gradle wrapper (`gradlew` + `gradle-wrapper.jar`).
+2. Connect a device or start an emulator and press **Run**.
 
-Of vanaf de command line (na `gradle wrapper` één keer):
+Or from the command line (after `gradle wrapper` once):
 
 ```bash
-./gradlew assembleDebug        # debug-APK, geen signing nodig
-./gradlew assembleRelease      # release-APK, vereist signing (zie onder)
+./gradlew assembleDebug        # debug APK, no signing required
+./gradlew assembleRelease      # release APK, requires signing (see below)
 ```
 
-De release-APK verschijnt in `app/build/outputs/apk/release/`.
+The release APK ends up in `app/build/outputs/apk/release/`.
 
-## Signing key aanmaken
+## Creating a signing key
 
-Nodig voor release-builds (en dus voor updates die elkaar kunnen overschrijven).
+Required for release builds (and therefore for updates that can overwrite each other).
 
 ```bash
 keytool -genkey -v -keystore release.jks -keyalg RSA -keysize 2048 \
         -validity 10000 -alias paperscan
 ```
 
-Bewaar `release.jks` **veilig en buiten git** (staat al in `.gitignore`).
+Keep `release.jks` **safe and out of git** (already in `.gitignore`).
 
-Voor lokale release-builds maak je een `keystore.properties` in de projectroot
-(zie `keystore.properties.example`):
+For local release builds, create a `keystore.properties` in the project root
+(see `keystore.properties.example`):
 
 ```properties
-storeFile=/pad/naar/release.jks
+storeFile=/path/to/release.jks
 storePassword=...
 keyAlias=paperscan
 keyPassword=...
 ```
 
-## Bouwen via Gitea Actions
+## Building via Gitea Actions
 
-De workflow `.gitea/workflows/build.yml` bouwt een getekende release-APK bij elke
-versietag (`git tag v0.1.0 && git push --tags`) of via een handmatige run.
+The workflow `.gitea/workflows/build.yml` builds a signed release APK on every version tag
+(`git tag v0.1.0 && git push --tags`) or via a manual run, and publishes it as a **Release**
+with the APK attached as a downloadable asset.
 
-Zet in je Gitea-repo onder **Settings → Actions → Secrets** deze secrets klaar:
+Add these secrets under **Settings → Actions → Secrets** in your Gitea repo:
 
-| Secret | Inhoud |
+| Secret | Contents |
 | --- | --- |
-| `SIGNING_KEYSTORE_BASE64` | `base64 -w0 release.jks` (de keystore als base64) |
-| `SIGNING_STORE_PASSWORD` | wachtwoord van de keystore |
-| `SIGNING_KEY_ALIAS` | bv. `paperscan` |
-| `SIGNING_KEY_PASSWORD` | wachtwoord van de sleutel |
+| `SIGNING_KEYSTORE_BASE64` | `base64 -w0 release.jks` (the keystore as base64) |
+| `SIGNING_STORE_PASSWORD` | keystore password |
+| `SIGNING_KEY_ALIAS` | e.g. `paperscan` |
+| `SIGNING_KEY_PASSWORD` | key password |
 
-De build gebruikt env-vars, dus er komt niets gevoeligs in de repo terecht. De APK
-komt als artifact `paperscan-release` beschikbaar bij de workflow-run.
+The build uses env vars, so nothing sensitive ends up in the repo.
 
-> Zorg dat je Gitea Actions-runner Docker-images kan trekken (`mingc/android-build-box`).
+> The build runs in a container (`mingc/android-build-box`), so the Actions runner must be
+> **x86_64** — the Android build tools (aapt2) are x86_64-Linux only and won't run natively
+> on an ARM64 runner.
 
-## Paperless-ngx instellen (in de app)
+## Setting up Paperless-ngx (in the app)
 
-1. Maak in Paperless een API-token aan: **Instellingen → profiel → API-token**
-   (of via `/api/token/`).
-2. Open in PaperScan het tandwiel → vul **server-URL** (bv. `https://paperless.thuis.lan`)
-   en het **token** in → **Verbinding testen** → **Opslaan**.
+1. Create an API token in Paperless: **Settings → profile → API token** (or via `/api/token/`).
+2. In PaperScan, open the gear icon → enter the **server URL** (e.g. `https://paperless.home.lan`)
+   and the **token** → **Test connection** → **Save**.
 
-Gebruik bij voorkeur **https**; bij `http://` waarschuwt de app dat token en documenten
-onversleuteld over het netwerk gaan.
+Prefer **https**; with `http://` the app warns that the token and documents travel over the
+network unencrypted.
 
-## Projectstructuur
+## Project layout
 
 ```
 app/src/main/java/eu/geyskens/pdfscan/
-├── PaperScanApp.kt          # Application; laadt OpenCV native libs
-├── MainActivity.kt          # Compose host + navigatie
-├── ScanViewModel.kt         # scan-sessie, rendering, export, upload
-├── data/                    # Page-model, ScanFilter, SettingsRepository
+├── PaperScanApp.kt          # Application; loads OpenCV native libs
+├── MainActivity.kt          # Compose host + navigation
+├── ScanViewModel.kt         # scan session, rendering, export, upload
+├── data/                    # Page model, ScanFilter, SettingsRepository
 ├── scan/                    # EdgeDetector, ImageProcessor, BitmapIo (OpenCV)
 ├── pdf/                     # PdfBuilder (multi-page PDF)
-├── paperless/               # PaperlessClient (OkHttp REST)
+├── paperless/               # PaperlessClient (OkHttp REST + task polling)
 └── ui/screens/              # Camera, Pages, Crop, Export, Settings
 ```
 
-## Roadmap / ideeën
+## Roadmap
 
-- Live randdetectie-overlay tijdens het richten (nu bij vastleggen)
-- OCR-tekstlaag (bv. Tesseract) volledig on-device
-- Batch-import van bestaande foto's uit de galerij
+Tracked as issues in the repository:
+
+- Live edge-detection overlay while aiming (like Microsoft Lens)
+- Internationalization: extract UI strings to resources + add translations
+- Batch import scans from the gallery
+
+> OCR is intentionally **not** done on-device: Paperless-ngx already runs OCR (via
+> OCRmyPDF/Tesseract) when it consumes the uploaded document.