Set up project skeleton (milestone 1)

- Architecture and feature overview in docs/ARCHITECTURE.md
- Gradle 9.8 / AGP 9.4 / Kotlin 2.4 with version catalog and convention plugins
- Modules :app, :core:*, :device-profiles, :feature:* (placeholder screens)
- Flavors core (no INTERNET, enforced by a build check) and full
- Material You theme, navigation, expert mode and dry-run settings (DataStore)
- Pixel 8-10 device detection, unit tests, GPLv3 license, English README with Obtainium badge

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

README.md

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+# Pixelwall
+
+Privacy and hardening app for Google Pixel phones (Pixel 8 – 10, Android 15/16, no root).
+Audit your device, fine-tune permissions and settings, and undo every change.
+
+[<img src="https://raw.githubusercontent.com/ImranR98/Obtainium/main/assets/graphics/badge_obtainium.png" alt="Get it on Obtainium" height="80">](https://apps.obtainium.imranr.dev/redirect?r=obtainium://add/https://git.mrblake.cc/MrBlake/Pixelwall)
+
+> Status: early development (milestone 1 of 9). Architecture and roadmap: [docs/ARCHITECTURE.md](docs/ARCHITECTURE.md) (German).
+
+## Install
+
+Install and update through [Obtainium](https://obtainium.imranr.dev) with the button above, or add
+`https://git.mrblake.cc/MrBlake/Pixelwall` as an app source. Releases ship two APKs: pick `core`
+(no network permission) or `full` with Obtainium's APK filter. No releases yet, the first one follows at the end of the roadmap.
+
+## Build variants
+
+| Flavor | applicationId | Network |
+|---|---|---|
+| `core` | `org.pixelwall.app` | no `INTERNET` permission (enforced by `./gradlew check`) |
+| `full` | `org.pixelwall.app.full` | `INTERNET` for the DNS filter and optional rule updates |
+
+## Building
+
+Requirements: JDK 21, Android SDK (platform 37).
+
+```sh
+./gradlew assembleCoreDebug      # debug APK without network access
+./gradlew check                  # unit tests, lint, network permission check
+```
+
+## License
+
+GPLv3, see [LICENSE](LICENSE).