Free days, vacation forfeiture, and global auto-replanning

Free days (Sat/Sun/red days, subject to DayOverride) can never be
vacation, and can only be parental leave when the workspace opts in via
take_pl_on_red_days. The allocator already honoured this; the hand-pin
path bypassed it entirely.

- PlanningService gains optional workspace_repo/day_override_repo deps
  and _reject_illegal_free_day, enforced in add_planned_day and update.
  Reuses allocation_service.is_free_day rather than re-deriving it, and
  no-ops when the deps are unset so existing callers are unaffected.
- update_planned_day had no ValidationError handler at all, so a
  validation failure there 500'd instead of 422'ing. Fixed.
- Calendar filters the pin write loop by the day's isFree; the modal
  explains free days stay off, and that pinning opts a day out of
  automatic re-planning.

Vacation days at risk of forfeiture were computed and sent over the
wire but never rendered: an at-risk column with the age-out/over-cap
split, and a dashboard key figure.

PlanProposal.warnings was likewise parsed but rendered nowhere, for all
three kinds. Adds PlanWarningCard in a Risks section above the tips,
with parent names resolved and dates formatted.

POST /api/plan/sync now fires from the workspace layer on every
plan-input change rather than only from Calendar, so a Settings edit or
a pinned-day save re-plans day types instead of merely refetching.
Overlapping bumps coalesce into one trailing run; a rejection cannot
wedge the in-flight guard. eviction_preview was silently dropped by the
frontend despite always being on the wire, and is now surfaced through
context.

Verified: backend 890 passed (91.49% coverage), frontend 1297 passed,
ruff/eslint/tsc clean. Browser-checked in Swedish and English.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JVQx4NUvPbJhn6UcvRd2QY

frontend/src/pages/Dashboard.tsx

@@ -24,6 +24,7 @@ import { KeyFigures } from '@/components/dashboard/KeyFigures'
 import { Age4Bars } from '@/components/dashboard/Age4Bars'
 import { YearRows } from '@/components/dashboard/YearRows'
 import { SurplusAdviceTip } from '@/components/dashboard/SurplusAdviceTip'
+import { PlanWarningCard } from '@/components/dashboard/PlanWarningCard'
 import { ParentalLeaveBreakdown } from '@/components/dashboard/ParentalLeaveBreakdown'
 import { TipCard } from '@/components/inputs/TipCard'
 import { Onboarding } from '@/pages/Onboarding'
@@ -133,6 +134,20 @@ export function Dashboard(): ReactNode {
   // the combined total, so skip the breakdown in that case.
   const showPerParentExpiring = parentProjections.length > 1
 
+  // Vacation days forecast lost (age-out or over the carry-forward cap),
+  // across every parent, from this year onward — a past year's loss already
+  // happened and is no longer actionable (same guard `YearRows` uses for
+  // its own per-year expiring figure).
+  const currentYear = new Date().getFullYear()
+  const vacationAtRisk = parentProjections.reduce(
+    (sum, projection) =>
+      sum +
+      projection.yearBalances
+        .filter((balance) => balance.year >= currentYear)
+        .reduce((yearSum, balance) => yearSum + balance.vacation.expiring, 0),
+    0,
+  )
+
   const parentDisplayName = (uuid: string, index: number): string => {
     const resolved = membersLoading ? uuid : nameFor(uuid)
     return resolved === uuid
@@ -217,6 +232,7 @@ export function Dashboard(): ReactNode {
   }))
 
   const surplusAdvice = proposal?.surplusAdvice ?? []
+  const warnings = proposal?.warnings ?? []
   const hasTips = (tips?.length ?? 0) > 0 || surplusAdvice.length > 0
   const heroRemedy = deriveHeroRemedy(tips)
 
@@ -254,6 +270,7 @@ export function Dashboard(): ReactNode {
             daysLeft={analytics.combinedDaysLeft}
             daysUsed={analytics.combinedDaysUsed}
             expiringAtB4={analytics.combinedExpiringAtB4}
+            vacationAtRisk={vacationAtRisk}
           />
         )}
 
@@ -278,6 +295,17 @@ export function Dashboard(): ReactNode {
           </section>
         )}
 
+        {warnings.length > 0 && (
+          <section className="dashboard__section" data-testid="dashboard-warnings">
+            <h2>{t('planWarnings.sectionTitle')}</h2>
+            <div className="dashboard__tips-list">
+              {warnings.map((warning, index) => (
+                <PlanWarningCard key={`${warning.kind}-${index}`} warning={warning} nameFor={nameForAdvice} index={index} />
+              ))}
+            </div>
+          </section>
+        )}
+
         {hasTips && (
           <section className="dashboard__section" data-testid="dashboard-tips">
             <h2>{t('tips.title')}</h2>