Redesign the setup flow and consolidate the CSS into one primitives layer

Onboarding asks explicitly for one or two parents and shows one card per
parent for balances; the balance form is per parent with inline
validation; the partner can be filled from the FK deduction or added
from it. Settings and Dashboard reuse the same form.

CSS: bare buttons carry no colour any more; buttons, cards, choice
cards, fields, alerts, badges, eyebrow and modal chrome are defined once
in primitives.css. Media queries live only in responsive.css. A style
guard test blocks hex, !important and stray media queries. Bilingual
fixes: calendar selects size by content, header no longer wraps. Vitest
is capped at four workers.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

frontend/src/i18n/en/settings.ts

@@ -14,24 +14,27 @@ export const settings = {
   'dayOverridesInput.offStatus': 'I\'m off this day',
   'dayOverridesInput.statusLegend': 'Status',
   'dayOverridesInput.workingStatus': 'I\'m working this day',
-  'manualFetchModal.cancelButton': 'Cancel',
-  'manualFetchModal.closeAria': 'Close',
-  'manualFetchModal.daysRemaining': 'Days remaining:',
-  'manualFetchModal.daysUsedLabel': 'Days used',
-  'manualFetchModal.description': 'Enter your parental leave information from Försäkringskassan manually if automatic fetching is unavailable.',
-  'manualFetchModal.dubbeldagarLabel': 'Dubbeldagar left (0-60)',
-  'manualFetchModal.lagstaUsedLabel': 'Lägstanivå (minimum-rate, 90-day tier) used',
-  'manualFetchModal.remainingBreakdownTitle': 'Remaining Days Breakdown',
-  'manualFetchModal.reservedDaysLabel': 'Reserved days left',
-  'manualFetchModal.saveButton': 'Save',
-  'manualFetchModal.saveError': 'Failed to save manual data',
-  'manualFetchModal.savingButton': 'Saving…',
-  'manualFetchModal.sjukpenningUsedLabel': 'Sjukpenningnivå (income-based, 390-day tier) used',
-  'manualFetchModal.tierBreakdownTitle': 'Tier Breakdown',
-  'manualFetchModal.title': 'Enter Parental Leave Data',
-  'manualFetchModal.totalDaysLabel': 'Total days (0-480)',
-  'manualFetchModal.totalDaysSectionTitle': 'Total Days',
-  'manualFetchModal.transferableDaysLabel': 'Transferable days left',
+  'parentBalance.advancedToggle': 'Advanced',
+  'parentBalance.cancelButton': 'Cancel',
+  'parentBalance.closeAria': 'Close',
+  'parentBalance.description': 'The figures are on Mina sidor at Försäkringskassan, under Föräldrapenning.',
+  'parentBalance.dubbeldagarHelper': 'Shared by both parents together, during the first 15 months.',
+  'parentBalance.dubbeldagarLeftLabel': 'Dubbeldagar left (0-60)',
+  'parentBalance.invalid': 'The total (sjukpenningnivå + lägstanivå) can\'t exceed {total} days.',
+  'parentBalance.lagstaLeftLabel': 'Lägstanivå (minimum-rate tier) left (0-90)',
+  'parentBalance.loadingBalance': 'Loading balance…',
+  'parentBalance.presetButton': 'No days taken yet',
+  'parentBalance.rangeError': 'Enter a number between {min} and {max}.',
+  'parentBalance.reservedExceedsError': 'Reserved days can\'t exceed the sjukpenningnivå + lägstanivå days left.',
+  'parentBalance.reservedLeftHelper': 'Leave empty and we\'ll calculate it.',
+  'parentBalance.reservedLeftLabel': 'Reserved days left (0-90)',
+  'parentBalance.saveButton': 'Save',
+  'parentBalance.saveError': 'Failed to save the remaining days',
+  'parentBalance.savingButton': 'Saving…',
+  'parentBalance.sjukpenningLeftLabel': 'Sjukpenningnivå (income-based tier) left (0-390)',
+  'parentBalance.summary': '= {left} of {total} days left',
+  'parentBalance.title': '{name}\'s days left',
+  'parentBalance.titleSelf': 'Your days left',
   'parentProfileInput.employed': 'Employed',
   'parentProfileInput.employmentStatusLabel': 'Employment status',
   'parentProfileInput.hourly': 'Hourly wage',
@@ -57,6 +60,7 @@ export const settings = {
   'settings.addPartnerError': 'Could not add partner',
   'settings.addPartnerSuccess': 'Partner added!',
   'settings.addingPartner': 'Adding...',
+  'settings.balanceButton': 'Days left',
   'settings.calendarSectionTitle': 'Calendar',
   'settings.cancelButton': 'Cancel',
   'settings.childBirthDateLabel': 'Child\'s birth date',
@@ -78,8 +82,6 @@ export const settings = {
   'settings.partnerNamePlaceholder': 'Partner\'s name',
   'settings.partnerNameRequired': 'Enter a name for the partner',
   'settings.partnerSectionTitle': 'Partner',
-  'settings.planningHelp': 'Your planning goal, and whether you plan alone or together with a partner, control how the planner suggests distributing days.',
-  'settings.planningSectionTitle': 'Planning',
   'settings.preschoolHelp': 'Preschools usually close for about 6 days a year for planning. Enter how many days your preschool has, so they are reserved in the plan.',
   'settings.preschoolPlanningDaysLabel': 'Preschool planning days per year',
   'settings.profileHelp': 'Your salary type and employment status are used to estimate your SGI and plan your leave.',
@@ -102,9 +104,6 @@ export const settings = {
   'settings.saveChildButton': 'Save child\'s details',
   'settings.saveChildError': 'Could not save the child\'s details',
   'settings.saveChildSuccess': 'Child\'s details saved!',
-  'settings.savePlanningButton': 'Save planning',
-  'settings.savePlanningError': 'Could not save planning settings',
-  'settings.savePlanningSuccess': 'Planning settings saved!',
   'settings.saveProfileButton': 'Save your profile',
   'settings.saveProfileError': 'Could not save your profile',
   'settings.saveProfileSuccess': 'Your profile was saved!',