feat: v0.5.0 - provider icon actions, duplicate & connectivity test, dashboard chart fixes

- ProviderList: icon buttons (edit/copy/test/delete) via lucide-react, speed-test badge before enable/switch button
- Duplicate provider: deep-copy provider + models as xxx-copy
- test_connectivity command (cc-switch semantics: GET base_url, any HTTP response = reachable), latency badge green/orange/red, auto-dismiss 6s
- Dashboard: daily bars anchored to panel bottom, Card flex height fix (heatmap stays content-height)

src-tauri/tauri.conf.json

@@ -1,6 +1,6 @@
 {
   "productName": "Kimi Switch",
-  "version": "0.4.1",
+  "version": "0.5.0",
   "identifier": "com.kimiswitch.app",
   "build": {
     "beforeDevCommand": "npm run dev",