Update version number to 2.0.6 across codebase

- Fix version inconsistencies in server.js API status endpoint
- Update User-Agent string in RSS feed manager
- Update version in config file templates
- Update dashboard display with version 2.0.6
- Add version 2.0.6 to version history with changelog

🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>

server.js

@@ -397,7 +397,7 @@ app.get('/api/status', authenticateJWT, async (req, res) => {
     res.json({
       success: true,
       status: 'running',
-      version: '1.2.0',
+      version: '2.0.6',
       transmissionConnected: transmissionStatus.connected,
       transmissionVersion: transmissionStatus.version,
       transmissionStats: {