feat: Add container restart functionality from web UI

- Added restart button to settings page
- Created /api/restart endpoint (file-flag based)
- Implemented watch-restart.sh daemon
- Added systemd service for restart watcher
- Updated README with restart setup instructions
- Container automatically restarts when settings changed

Settings flow:
1. User edits settings in web UI
2. Click 'Save Settings' to persist to .env
3. Click 'Restart Bot' to apply changes
4. Watcher detects flag and restarts container
5. New settings loaded automatically

README.md

@@ -178,6 +178,24 @@ POST /api/trading/check-risk
 # Get current settings
 GET /api/settings
 
+# Update settings
+POST /api/settings
+{
+  "MAX_POSITION_SIZE_USD": 100,
+  "LEVERAGE": 10,
+  "STOP_LOSS_PERCENT": -1.5,
+  ...
+}
+
+# Restart bot container (apply settings)
+POST /api/restart
+```
+
+**Notes:**
+- Settings changes require container restart to take effect
+- Use the web UI's "Restart Bot" button or call `/api/restart`
+- Restart watcher must be running (see setup below)
+
 # Update settings
 POST /api/settings
 {
@@ -223,6 +241,26 @@ docker compose restart trading-bot
 docker compose down
 ```
 
+### Restart Watcher (Required for Web UI Restart Button)
+The restart watcher monitors for restart requests from the web UI:
+
+```bash
+# Start watcher manually
+cd /home/icke/traderv4
+nohup ./watch-restart.sh > logs/restart-watcher.log 2>&1 &
+
+# OR install as systemd service (recommended)
+sudo cp trading-bot-restart-watcher.service /etc/systemd/system/
+sudo systemctl daemon-reload
+sudo systemctl enable trading-bot-restart-watcher
+sudo systemctl start trading-bot-restart-watcher
+
+# Check watcher status
+sudo systemctl status trading-bot-restart-watcher
+```
+
+The watcher enables the "Restart Bot" button in the web UI to automatically restart the container when settings are changed.
+
 ### Environment Variables
 All settings are configured via `.env` file:
 - Drift wallet credentials