Cash-Anfangswert (erste Lebensphase) editierbar

Neues Feld Plan.initialCash (additiv, Default 0). computePlan startet die erste Phase
mit diesem Cash-Bestand statt 0. In der Matrix ist die Cash-Zelle der ersten Phase
klickbar und oeffnet ein Popup zum Setzen des Anfangswerts (PATCH /api/plans/{id}).
Szenario-Kopie uebernimmt den Wert. Golden-Test ergaenzt.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/components/PlanView.tsx

@@ -29,6 +29,7 @@ import {
 } from "@/components/ElementDetail";
 import { PhaseDetail } from "@/components/PhaseDetail";
 import { PlanProfileFields, type ProfileDraft } from "@/components/PlanProfileFields";
+import { MoneyField } from "@/components/FormField";
 import { api } from "@/lib/api-client";
 import { formatChf } from "@/lib/format";
 import {
@@ -94,6 +95,7 @@ export function PlanView({
   const [reviewFromPhaseId, setReviewFromPhaseId] = useState<string | null>(null);
   const [editTransition, setEditTransition] = useState<{ elementId: string; fromPhaseId: string } | null>(null);
   const [editPhaseCell, setEditPhaseCell] = useState<{ elementId: string; phaseId: string } | null>(null);
+  const [showCashInit, setShowCashInit] = useState(false);
 
   const columns = useMemo<Column[]>(() => {
     const cols: Column[] = [];
@@ -332,13 +334,16 @@ export function PlanView({
                   </span>
                   <span className="text-[10px] text-faint">verfuegbares Kapital</span>
                 </td>
-                {columns.map((col) =>
-                  col.kind === "phase" ? (
+                {columns.map((col) => {
+                  const isFirst = col.kind === "phase" && col.phase.sequenceNumber === 1;
+                  return col.kind === "phase" ? (
                     <td
                       key={`cash-${col.phase.id}`}
+                      onClick={isFirst ? () => setShowCashInit(true) : undefined}
+                      title={isFirst ? "Cash-Anfangswert bearbeiten" : undefined}
                       className={`border-b border-r border-border px-2 py-1.5 text-center text-xs ${
-                        col.phase.cashNegative ? "font-semibold text-danger" : "text-fg"
-                      }`}
+                        isFirst ? "cursor-pointer hover:bg-accent-soft" : ""
+                      } ${col.phase.cashNegative ? "font-semibold text-danger" : "text-fg"}`}
                     >
                       <span className="whitespace-nowrap">
                         {formatChf(col.phase.cashStart)} <span className="text-faint">→</span> {formatChf(col.phase.cashEnd)}
@@ -348,8 +353,8 @@ export function PlanView({
                     <td key={`cash-t-${col.fromPhase.id}`} className="border-b border-r border-border px-2 py-1.5 text-center text-[11px] text-faint">
                       →
                     </td>
-                  )
-                )}
+                  );
+                })}
               </tr>
               {CATEGORY_ORDER.map((cat) => {
                 const els = elementsByCategory.get(cat)!;
@@ -475,6 +480,17 @@ export function PlanView({
         />
       )}
 
+      {showCashInit && (
+        <CashInitialDialog
+          plan={plan}
+          onClose={() => setShowCashInit(false)}
+          onSaved={() => {
+            setShowCashInit(false);
+            onChanged();
+          }}
+        />
+      )}
+
       {reviewFromPhaseId && (() => {
         const fromPhase = computed.phases.find((p) => p.id === reviewFromPhaseId);
         if (!fromPhase) return null;
@@ -1038,6 +1054,35 @@ function TransitionReviewDialog({
   );
 }
 
+// --- Dialog: Cash-Anfangswert (erste Lebensphase) ---
+function CashInitialDialog({ plan, onClose, onSaved }: { plan: PlanInput; onClose: () => void; onSaved: () => void }) {
+  const [value, setValue] = useState(plan.initialCash);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  async function save() {
+    setSaving(true);
+    setError(null);
+    try {
+      await api.patch(`/api/plans/${plan.id}`, { initialCash: value });
+      onSaved();
+    } catch (e) {
+      setError(e instanceof Error ? e.message : "Speichern fehlgeschlagen.");
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  return (
+    <DialogShell title="Cash-Anfangswert" onClose={onClose}>
+      <p className="text-sm text-muted">Startbestand des Cash-Kontos zu Beginn der ersten Lebensphase.</p>
+      <MoneyField label="Anfangswert (CHF)" value={value} onChange={setValue} />
+      {error && <p className="text-sm text-danger">{error}</p>}
+      <DialogActions saving={saving} onConfirm={save} onClose={onClose} confirmLabel="Speichern" />
+    </DialogShell>
+  );
+}
+
 // --- Dialog: Element-Werte einer Lebensphase (per Klick auf eine Phasenzelle) ---
 function PhaseCellDialog({
   element,