Create an email template for sending a high-level project summary to executive stakeholders. The email should summarize the project's key achievements, upcoming milestones, and any major risks or challenges. Include placeholders for [Project Name], [Key Achievements], [Upcoming Milestones], [Major Risks], and [Executive Summary]. The email should have a formal and concise tone, using bullet points and bolded headers to make the information digestible and action-oriented.