docs: add live demo banner to README + complete wiki (9 pages)

README:
- Added prominent live demo banner at the top with links to
  https://evershelfproject.dadaloop.it/demo and project website

Wiki (docs/wiki/):
- Home.md         — overview, table of contents, what's new
- Installation.md — Docker, Apache, Nginx, HTTPS, cron, backup
- Configuration.md — full .env reference, settings UI, rate limits
- Features.md     — complete feature documentation
- API-Reference.md — all REST endpoints with params/responses
- Android-Kiosk.md — setup wizard, permissions, troubleshooting
- Scale-Gateway.md — BLE protocol, setup, troubleshooting
- Translations.md  — how to add/edit language files
- Contributing.md  — dev workflow, branch strategy, CI, code style
- FAQ.md           — common issues and solutions

docs/wiki/Home.md

@@ -0,0 +1,93 @@
+# 🏠 EverShelf Wiki
+
+Welcome to the **EverShelf** project wiki — your complete reference for installation, configuration, features, and development.
+
+---
+
+## 🚀 Try it now
+
+> **[▶ Live Demo](https://evershelfproject.dadaloop.it/demo)** — no installation, no login, full AI enabled  
+> **[🌐 Project Website](https://evershelfproject.dadaloop.it/)**
+
+---
+
+## 📚 Wiki Contents
+
+| Page | Description |
+|------|-------------|
+| [Installation](Installation) | Docker, manual setup, HTTPS, web server config |
+| [Configuration](Configuration) | `.env` reference — all options explained |
+| [Features](Features) | Complete feature documentation |
+| [API Reference](API-Reference) | All REST endpoints, parameters, and responses |
+| [Android Kiosk](Android-Kiosk) | Tablet kiosk app setup and usage |
+| [Scale Gateway](Scale-Gateway) | BLE smart scale integration |
+| [Translations](Translations) | Adding and editing language files |
+| [Contributing](Contributing) | Development workflow and PR process |
+| [FAQ & Troubleshooting](FAQ) | Common issues and solutions |
+
+---
+
+## ✨ What is EverShelf?
+
+EverShelf is a **self-hosted pantry management system** that runs entirely on your own server. It:
+
+- Tracks food inventory across multiple storage locations (pantry, fridge, freezer, custom)
+- Scans barcodes and uses **Google Gemini AI** to identify products from photos
+- Suggests recipes based on what's in your pantry — especially items about to expire
+- Predicts what you'll need to buy before you run out
+- Integrates with the **Bring!** shopping list app
+- Supports a **BLE smart scale** for weight-based tracking
+- Runs as a **Progressive Web App** installable on any device
+- Optionally pairs with a dedicated **Android kiosk tablet app**
+
+All data stays on your server. No cloud, no subscriptions.
+
+---
+
+## 🆕 What's New
+
+### v1.7.1 (2026-05-04)
+- Destructive actions ("Butta tutto", "Finisci tutto") now require a **5-second countdown confirmation** before executing
+- History undo button ↩ is now clearly visible (red tint, larger)
+- Undo confirmation uses the in-app modal instead of the native browser `confirm()`
+
+### v1.7.0 (2026-05-04)
+- Smart auto-discovery rewrite (kiosk)
+- Gateway auto-pre-configuration after install
+- ErrorReporter init at setup start
+- Graceful Bring! no-key state
+- Use-quantity guard with shake animation
+- Demo mode (`?demo=1`)
+
+→ See the full [CHANGELOG](https://github.com/dadaloop82/EverShelf/blob/main/CHANGELOG.md)
+
+---
+
+## 📦 Repository Structure
+
+```
+EverShelf/
+├── index.html                  # Single-page application entry point
+├── manifest.json               # PWA manifest
+├── .env.example                # Configuration template
+├── api/
+│   ├── index.php               # Main API router
+│   ├── database.php            # SQLite schema + migrations
+│   └── cron_smart_shopping.php # Background predictions job
+├── assets/
+│   ├── css/style.css
+│   ├── js/app.js
+│   └── img/
+├── translations/               # i18n JSON files (it, en, de)
+├── docs/openapi.yaml           # OpenAPI 3.0 spec
+├── evershelf-kiosk/            # Android kiosk app (Kotlin)
+└── evershelf-scale-gateway/    # Android BLE gateway app (Kotlin)
+```
+
+---
+
+## 📄 License
+
+MIT — free to use, modify, and distribute. See [LICENSE](https://github.com/dadaloop82/EverShelf/blob/main/LICENSE).
+
+**Author:** Stimpfl Daniel — [evershelfproject@gmail.com](mailto:evershelfproject@gmail.com)