tui: show real-time MCP server status in home screen with connection state indicators

- Displays MCP servers with visual status indicators (connected/failed/disabled)
- Shows error messages for failed connections to help users troubleshoot
- Replaces static help text with dynamic keybind display that updates based on user config
- Adds weather and puppeteer MCP servers to example configuration

opencode.json

@@ -1,3 +1,13 @@
 {
-  "$schema": "https://opencode.ai/config.json"
+  "$schema": "https://opencode.ai/config.json",
+  "mcp": {
+    "weather": {
+      "type": "local",
+      "command": ["bun", "x", "@h1deya/mcp-server-weather"]
+    },
+    "puppeteer": {
+      "type": "local",
+      "command": ["buns", "x", "puppeteer-mcp-server"]
+    }
+  }
 }