Tell parents how to save the days expiring at age 4

The dashboard stated the loss and stopped there. With Jacob at 48/48 savable
and 24 days over the cap, and Amelie at 3/48 with 45 days of headroom, those
24 days are not lost at all — transferring them before the 4th birthday saves
every one. The app never said so.

`_rule_age4_pooling_loss` already computed exactly that advice, bounded by the
FK-reported `transferable_days_left`, in finished Swedish and English. It never
ran: `age4_pooling_tip_min_child_age_years` held it back until the child turned
2. The calendar IS the plan, so gate on the plan instead — the noise case is a
newborn with nothing planned, not a young child whose parents have planned in
detail. `age4_pooling_tip_min_planned_days` (20) replaces the age gate.

Both variants drop to `info`. A projection four years out should not read as a
verdict on the user's planning; the hero carries the alarm, this card carries
the advice. The copy now leads with "plans change, this is only a projection"
and closes by pointing at keeping balances up to date, since parents will come
back and record what they actually took.

- Suppress `preserve_for_age_4` whenever `age4_pooling_loss` fires for the same
  child. The pooling tip states the same loss plus the remedy and the correct
  per-parent cap, so emitting both gave two contradictory "you're losing N
  days" figures.
- `preserve_for_age_4` now sends `parent_cap` and its copy interpolates it. It
  claimed "only 96 days can be saved" — false for a two-parent family, where
  the cap is 48 each, as the Age4Bars card two rows below already showed.
- The hero grows a "How to save them" line derived from the tip itself, so the
  two can never disagree on the number. Dismissing the tip retires both.
- "Försäkringskassan" in that line links to FK's BankID login carrying a `goto`
  to Min föräldrapenning — the e-service showing "Dagar ni kan föra över" —
  so the transfer is one click away. `translate()` returns a plain string and
  word order differs between locales, so the anchor's position travels inside
  the template as `{fk}` and the rendered string is split around it.

Verified in the browser: hero, link target, tip severity and the absence of
`preserve_for_age_4`, in both languages and at 390px. Note the demo seed cannot
reach this shape — it gives the surplus parent no FK snapshot at all.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DXPBfr1v7F71t6QcbHCaaT

frontend/src/styles/components.css

@@ -38,6 +38,18 @@
   color: var(--c-text);
 }
 
+.dashboard-hero__remedy {
+  margin: var(--sp-2) 0 0;
+  max-width: 72ch;
+  font-size: var(--fs-sm);
+  color: var(--c-text-muted);
+}
+
+.dashboard-hero__remedy-label {
+  font-weight: 500;
+  color: var(--c-text);
+}
+
 /* One muted line under the hero while the figures still rest on the
  * statutory assumption for at least one parent. The lead word (the e2e
  * hook) is the only emphasised part. */