Implement opal-task Phases 6-8: Complete CLI Implementation

Phase 6: Display and Basic Commands
- Add display.go with colored formatting for tasks, projects, tags
- Implement cmd/root.go with Cobra command structure
- Implement cmd/list.go for listing and filtering tasks
- Implement cmd/add.go with support for regular and recurring tasks
- Implement cmd/done.go with bulk completion and confirmation

Phase 7: Advanced Commands
- Implement cmd/modify.go for updating task attributes
- Implement cmd/delete.go with soft delete confirmation
- Implement cmd/start.go and cmd/stop.go for task timing
- Implement cmd/count.go for counting filtered tasks
- Implement cmd/projects.go and cmd/tags.go for aggregation

Phase 8: Integration and Polish
- Update main.go to use CLI commands
- Add colored output with fatih/color
- Format task lists with proper alignment
- Highlight overdue tasks in red, upcoming in yellow
- Test end-to-end workflow: add, list, done, recurring tasks
- Verify recurrence spawning works correctly

All CLI commands functional and tested!

opal-task/main.go

@@ -4,23 +4,15 @@ import (
 	"fmt"
 	"os"
 
+	"git.jnss.me/joakim/opal/cmd"
 	"git.jnss.me/joakim/opal/internal/engine"
 )
 
 func main() {
-	// Initialize database
-	if err := engine.InitDB(); err != nil {
-		fmt.Fprintf(os.Stderr, "Error initializing database: %v\n", err)
-		os.Exit(1)
-	}
 	defer engine.CloseDB()
 
-	// Load config
-	if _, err := engine.LoadConfig(); err != nil {
-		fmt.Fprintf(os.Stderr, "Error loading config: %v\n", err)
+	if err := cmd.Execute(); err != nil {
+		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
 		os.Exit(1)
 	}
-
-	fmt.Println("Opal task manager initialized successfully!")
-	fmt.Println("Database and configuration ready.")
 }