feat: remove calendar and refine habits

frontend/src/lib/mvp-utils.test.ts

@@ -1,16 +1,31 @@
 import { describe, expect, it } from 'vitest'
-import { dateKey, isTaskView, moveDueDate } from './mvp-utils'
+import { dateKey, habitWeek, isHabitComplete, isTaskView, numericHabitInputValue } from './mvp-utils'
 
 describe('MVP view utilities', () => {
-  it('normalizes to UTC so stored due_at stays stable in every local timezone', () => {
-    const moved = moveDueDate('2026-09-05T14:30:00+08:00', '2026-09-09')
-    expect(moved).toBe('2026-09-09T14:30:00.000Z')
-    const newly = moveDueDate(null, '2026-09-09')
-    expect(newly).toBe('2026-09-09T09:00:00.000Z')
+  it('formats a local date as YYYY-MM-DD', () => {
+    expect(dateKey(new Date(2026, 8, 5))).toBe('2026-09-05')
+  })
+
+  it('returns the monday-to-sunday week containing the requested day', () => {
+    expect(habitWeek(new Date(2026, 8, 5)).map(dateKey)).toEqual([
+      '2026-08-31', '2026-09-01', '2026-09-02', '2026-09-03', '2026-09-04', '2026-09-05', '2026-09-06',
+    ])
   })
 
   it('identifies only task-backed views as task data loaders', () => {
     expect(['tasks', 'today', 'upcoming'].filter(isTaskView)).toEqual(['tasks', 'today', 'upcoming'])
-    expect(['calendar', 'habits', 'settings', 'trash'].filter(isTaskView)).toEqual([])
+    expect(['habits', 'settings', 'trash'].filter(isTaskView)).toEqual([])
+  })
+
+  it('only completes numeric habits when progress reaches the target', () => {
+    expect(isHabitComplete('numeric', 3, 5)).toBe(false)
+    expect(isHabitComplete('numeric', 5, 5)).toBe(true)
+    expect(isHabitComplete('boolean', 1, 5)).toBe(true)
+  })
+
+  it('does not invent a numeric value when the input is empty', () => {
+    expect(numericHabitInputValue(undefined)).toBeNull()
+    expect(numericHabitInputValue('')).toBeNull()
+    expect(numericHabitInputValue(4)).toBe(4)
   })
 })