feat: Improve cross-platform compatibility and connection reliability

- Add SSE keep-alive mechanism to prevent client timeout errors
- Store database in platform-specific application data directories:
  - macOS: ~/Library/Application Support/agent-browser/
  - Windows: %APPDATA%/agent-browser/
- Ensure proper data persistence when running as binary
- Improve cursor configuration for cross-platform support

Author: michiosw

internal/app/app.go

@@ -4,6 +4,8 @@ package app
 import (
 	"context"
 	"net/http"
+	"os"
+	"path/filepath"
 
 	"github.com/co-browser/agent-browser/internal/backend"
 	"github.com/co-browser/agent-browser/internal/backend/database"
@@ -38,8 +40,31 @@ var defaultServers = []DefaultServer{
 
 // provideDBConfig returns the database configuration.
 func provideDBConfig() database.Config {
+	// Get the platform-specific user config directory
+	userConfigDir, err := os.UserConfigDir()
+	if err != nil {
+		// Fallback to current directory if we can't get the config dir
+		return database.Config{
+			Path: "agent-browser.db",
+		}
+	}
+
+	// Create application-specific directory within the config dir
+	appDataDir := filepath.Join(userConfigDir, "agent-browser")
+
+	// Create directory if it doesn't exist
+	if err := os.MkdirAll(appDataDir, 0750); err != nil {
+		// Fallback to current directory if we can't create the app data dir
+		return database.Config{
+			Path: "agent-browser.db",
+		}
+	}
+
+	// Use platform-specific path for the database
+	dbPath := filepath.Join(appDataDir, "agent-browser.db")
+
 	return database.Config{
-		Path: "agent-browser.db", // TODO: Make this configurable via env vars
+		Path: dbPath,
 	}
 }
 

internal/mcp/server.go

@@ -4,6 +4,7 @@ package mcp
 import (
 	"context"
 	"fmt"
+	"time"
 
 	"github.com/co-browser/agent-browser/internal/events"
 	"github.com/co-browser/agent-browser/internal/log"
@@ -78,7 +79,10 @@ func NewMCPComponents(p MCPParams) (MCPResult, error) {
 	mcpServer.AddTool(tool, tools.HelloHandler)
 
 	// Create SSE server
-	sseServer := server.NewSSEServer(mcpServer)
+	sseServer := server.NewSSEServer(mcpServer,
+		server.WithKeepAlive(true),                   // Enable keep-alive to prevent client timeout
+		server.WithKeepAliveInterval(15*time.Second), // Send ping every 15 seconds
+	)
 
 	return MCPResult{
 		Server:      mcpServer,