fix: parse text output instead of JSON for plugin/MCP commands

- Remove --json flag from CLI commands (not supported)
- Parse plugin list text output format
- Parse MCP server list text output format
- Add status field to McpServerInfo for connection status
- Display connection status in MCP panel (✓/✗ badges)
- Simplify get_mcp_server to reuse list_mcp_servers

src/lib/components/McpManagementPanel.svelte

@@ -13,6 +13,7 @@
     url: string | null;
     transport: string; // "stdio", "http", or "sse"
     env: any | null;
+    status: string | null; // "Connected" or "Failed to connect"
   }
 
   const { onClose }: Props = $props();
@@ -178,6 +179,21 @@
                       class="w-4 h-4 {getTransportColor(server.transport)}"
                     />
                     {server.name}
+                    {#if server.status}
+                      {#if server.status.includes("Connected")}
+                        <span
+                          class="px-2 py-0.5 bg-[var(--success-color)]/20 text-[var(--success-color)] text-xs rounded border border-[var(--success-color)]/30"
+                        >
+                          ✓
+                        </span>
+                      {:else}
+                        <span
+                          class="px-2 py-0.5 bg-red-500/20 text-red-400 text-xs rounded border border-red-500/30"
+                        >
+                          ✗
+                        </span>
+                      {/if}
+                    {/if}
                   </h4>
                   <p class="text-xs text-[var(--text-secondary)] mt-1">
                     {server.transport.toUpperCase()}