[Feature] Overtime Warning System

[miniLV]

Overview

Alert users when they're working past their scheduled end time, showing the "cost" of overtime.

User Story

As someone who often works late, I want to see how much my overtime "costs" me, so that I can better value my personal time.

Acceptance Criteria

• Detect overtime state (current time > end time)
• Display overtime duration
• Show "opportunity cost" of overtime
• Visual indicator (different color/style)
• Optional notification when overtime starts

Overtime Calculation

// Overtime "loss" calculation
let overtimeMinutes = currentTime - endTime
let opportunityCost = overtimeMinutes × minuteRate

// Display: "You've worked 30 min overtime = ¥XX opportunity cost"

Visual Design

• Red/warning color theme for overtime state
• Countdown replaced with count-up timer
• "Loss" amount displayed prominently

Related Files

• Services/IncomeCalculationService.swift
• Views/Dashboard/CyberpunkDashboardView.swift
• Services/NotificationService.swift

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Priority: P2
Status: 📋 Planned (partial implementation exists)