UI enhancements, i18n, history drawer, and requested features

README.md

@@ -203,12 +203,11 @@ without losing the original.
 
 ### Recent generations
 
-The last 6 successful generations are saved in `localStorage` under
-`melodymuse-history`. Click any entry to restore both the **input form
+The last 500 successful generations are saved on the server. Click any entry to restore both the **input form
 values** AND the full **generated assets** — handy for comparing two
 generations of the same idea.
 
-Individual entries have an ✕ button to remove them. There's a **Clear all**
+Individual entries have an ✕ button to remove them. There's a **Clear history**
 button at the bottom of the history panel.
 
 ### Download the ZIP
@@ -393,6 +392,43 @@ provider, the key, or the prompts.
 | `LLM_MODEL` | | `MiniMax-M3` | |
 | `PORT` | | `3000` | |
 | `CORS_ORIGIN` | | `*` | Lock this down in production |
+| `DATA_DIR` | | `data` | Directory for persistent storage (e.g. `history.json`) |
+
+### Docker and History Persistence
+
+The application saves recent generations (history) to a file named `history.json` inside the directory specified by the `DATA_DIR` environment variable (defaults to `data` in the project root). 
+
+If you are running the application using Docker, any files written inside the container will be lost when the container is rebuilt or restarted. To ensure your history survives a Docker rebuild, you **must set up a Docker volume** mapped to the `DATA_DIR`.
+
+**Example using `docker run`:**
+```sh
+docker run -d \
+  -p 3000:3000 \
+  -e LLM_ENDPOINT="https://api.minimax.chat/v1" \
+  -e LLM_API_KEY="sk-..." \
+  -e DATA_DIR="/app/data" \
+  -v melodymuse-data:/app/data \
+  melodymuse-image
+```
+
+**Example using `docker-compose.yml`:**
+```yaml
+services:
+  melodymuse:
+    image: melodymuse-image
+    ports:
+      - "3000:3000"
+    environment:
+      - LLM_ENDPOINT=https://api.minimax.chat/v1
+      - LLM_API_KEY=sk-...
+      - DATA_DIR=/app/data
+    volumes:
+      - melodymuse-data:/app/data
+
+volumes:
+  melodymuse-data:
+```
+This ensures the `history.json` file is securely stored on your host machine and persists across rebuilds.
 
 ### Environment variables (Vite, dev only)
 
@@ -435,7 +471,7 @@ Response: `{ "style": "…", "mode": "…" }`.
 - The API key is held by the Node process via `process.env`. It's never
   sent to the browser in any response, not even in the health check.
 - The `localStorage` keys the SPA writes:
-  - `melodymuse-history` — last 6 generations
+  - `melodymuse-draft` — current unsaved input draft
   - `melodymuse-theme` — `'dark'` or `'light'`
   - `melodymuse-config` — reserved, currently unused (kept for future
     client-side server-URL override)