feat(reporting): restyle the Investment ledger

The scenario Investment ledger was a flat monochrome list. Give it a
visual hierarchy while keeping the reporting design vocabulary (quiet
navy-on-white, semantic green for benefits):
- lead with a Net cost hero block — the headline figure a board commits
  to — with gross/home and the gross · funding breakdown beneath it;
- turn the cost lines into a colour-keyed composition bar (navy → gold →
  grey, echoing the data-quality evidence bar) with matching dots;
- give annual benefits green icon-chip rows (they're recurring savings)
  and value-for-money its own iconography;
- add section and header icons throughout.

Purely presentational — same LedgerView data, no behaviour change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/portfolio/[slug]/(portfolio)/reporting/components/InvestmentLedger.tsx

@@ -6,7 +6,19 @@ import {
   TooltipProvider,
   TooltipTrigger,
 } from "@/app/shadcn_components/ui/tooltip";
-import { Info } from "lucide-react";
+import {
+  Info,
+  Wallet,
+  Coins,
+  Landmark,
+  Sprout,
+  Banknote,
+  Leaf,
+  Scale,
+  Gauge,
+  Cloud,
+  type LucideIcon,
+} from "lucide-react";
 import { moneyFull } from "./primitives";
 import { carsOffTheRoad, PROJECT_DELIVERY_RATE } from "@/lib/reporting/model";
 
@@ -25,108 +37,218 @@ export interface LedgerView {
   costPerCarbon: number;
 }
 
-function Row({
-  label,
-  value,
-  tip,
-  emphatic = false,
-  credit = false,
-  note,
-}: {
-  label: string;
-  value: string;
-  tip?: string;
-  emphatic?: boolean;
-  credit?: boolean;
-  note?: string;
-}) {
+const deliveryPct = Math.round(PROJECT_DELIVERY_RATE * 100);
+
+// The cost-composition palette echoes the data-quality evidence bar: quiet
+// navy → gold → grey, so the reporting surfaces read as one system.
+const COST_COLORS = {
+  construction: "#14163d",
+  delivery: "#a07c42",
+  contingency: "#c5cad8",
+} as const;
+
+function InfoDot({ label, tip }: { label: string; tip: string }) {
   return (
-    <div
-      className={`flex items-baseline justify-between gap-3 px-5 py-1.5 text-[0.84rem] ${
-        emphatic ? "mt-1 border-t border-gray-100 pt-2.5 pb-3" : ""
-      }`}
-    >
-      <span
-        className={`inline-flex items-center gap-1.5 ${emphatic ? "font-semibold text-gray-900" : "text-gray-500"}`}
-      >
-        {label}
-        {tip && (
-          <TooltipProvider delayDuration={100}>
-            <Tooltip>
-              <TooltipTrigger asChild>
-                <button
-                  type="button"
-                  aria-label={`About: ${label}`}
-                  className="inline-flex h-3.5 w-3.5 items-center justify-center rounded-full border border-gray-300 text-[0.62rem] text-gray-600 hover:text-gray-900"
-                >
-                  <Info className="h-2.5 w-2.5" />
-                </button>
-              </TooltipTrigger>
-              <TooltipContent className="max-w-[260px] text-xs leading-relaxed">
-                {tip}
-              </TooltipContent>
-            </Tooltip>
-          </TooltipProvider>
-        )}
-      </span>
-      <span
-        className={`whitespace-nowrap tabular-nums ${emphatic ? "font-semibold text-brandblue" : credit ? "font-semibold text-[#0c6b4a]" : "font-semibold text-brandblue"}`}
-      >
-        {value}
-        {note && <span className="font-normal text-gray-600"> · {note}</span>}
-      </span>
-    </div>
+    <TooltipProvider delayDuration={100}>
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <button
+            type="button"
+            aria-label={`About: ${label}`}
+            className="inline-flex h-3.5 w-3.5 items-center justify-center rounded-full border border-gray-300 text-gray-600 hover:text-gray-900"
+          >
+            <Info className="h-2.5 w-2.5" />
+          </button>
+        </TooltipTrigger>
+        <TooltipContent className="max-w-[260px] text-xs leading-relaxed">
+          {tip}
+        </TooltipContent>
+      </Tooltip>
+    </TooltipProvider>
   );
 }
 
-function GroupLabel({ children }: { children: React.ReactNode }) {
+function GroupLabel({
+  icon: Icon,
+  children,
+}: {
+  icon: LucideIcon;
+  children: React.ReactNode;
+}) {
   return (
-    <div className="px-5 pb-1 pt-3 text-[0.68rem] font-bold uppercase tracking-wide text-[#a07c42]">
+    <div className="flex items-center gap-1.5 px-5 pb-1.5 pt-4 text-[0.68rem] font-bold uppercase tracking-wide text-[#a07c42]">
+      <Icon className="h-3.5 w-3.5" />
       {children}
     </div>
   );
 }
 
-const deliveryPct = Math.round(PROJECT_DELIVERY_RATE * 100);
+/** A row led by an icon chip. `tone` tints benefits green, keeps the rest quiet. */
+function IconRow({
+  icon: Icon,
+  label,
+  value,
+  note,
+  tone = "neutral",
+}: {
+  icon: LucideIcon;
+  label: string;
+  value: string;
+  note?: string;
+  tone?: "neutral" | "benefit";
+}) {
+  const chip =
+    tone === "benefit"
+      ? "bg-[#e9f4ef] text-[#0c6b4a]"
+      : "bg-gray-50 text-gray-500";
+  const valueColor = tone === "benefit" ? "text-[#0c6b4a]" : "text-brandblue";
+  return (
+    <div className="flex items-center justify-between gap-3 py-1 text-[0.84rem]">
+      <span className="inline-flex items-center gap-2 text-gray-600">
+        <span
+          className={`inline-flex h-6 w-6 items-center justify-center rounded-md ${chip}`}
+        >
+          <Icon className="h-3.5 w-3.5" />
+        </span>
+        {label}
+      </span>
+      <span
+        className={`whitespace-nowrap tabular-nums font-semibold ${valueColor}`}
+      >
+        {value}
+        {note && <span className="font-normal text-gray-500"> · {note}</span>}
+      </span>
+    </div>
+  );
+}
 
 export function InvestmentLedger({ v }: { v: LedgerView }) {
+  const costParts = [
+    {
+      label: "Construction works",
+      value: v.constructionCost,
+      color: COST_COLORS.construction,
+    },
+    {
+      label: "Project delivery",
+      value: v.projectDelivery,
+      color: COST_COLORS.delivery,
+    },
+    {
+      label: "Contingency",
+      value: v.contingency,
+      color: COST_COLORS.contingency,
+    },
+  ];
+  const grossForBar = v.grossCost || 1;
+
   return (
     <div className="flex flex-col overflow-hidden rounded-lg border border-gray-200 bg-white">
-      <header className="px-5 pt-4">
+      <header className="flex items-center gap-2 px-5 pt-4">
+        <Wallet className="h-4 w-4 text-brandblue" />
         <h3 className="text-[0.88rem] font-semibold text-brandblue">
           Investment ledger
         </h3>
       </header>
 
-      <GroupLabel>Costs</GroupLabel>
-      <Row label="Construction works" value={moneyFull(v.constructionCost)} />
-      <Row label="Project delivery" value={moneyFull(v.projectDelivery)} />
-      <Row label="Contingency" value={moneyFull(v.contingency)} />
-      <Row label="Funding secured" value={`−${moneyFull(v.funding)}`} credit />
-      <Row
-        label="Net cost"
-        value={moneyFull(v.netCost)}
-        note={`${moneyFull(v.grossPerHome)} gross/home`}
-        emphatic
-        tip={`Gross cost = construction works + project delivery + contingency. Funding is deducted to give net. Excludes VAT and internal staff time. Project delivery is currently estimated at ${deliveryPct}% of construction.`}
-      />
+      {/* Net cost — the headline figure a board commits to. */}
+      <div className="mx-5 mt-3 rounded-lg border border-gray-100 bg-[#f6f7fb] px-4 py-3">
+        <div className="flex items-center justify-between">
+          <span className="inline-flex items-center gap-1 text-[0.68rem] font-bold uppercase tracking-wide text-gray-500">
+            Net cost
+            <InfoDot
+              label="Net cost"
+              tip={`Gross cost = construction works + project delivery + contingency. Funding is deducted to give net. Excludes VAT and internal staff time. Project delivery is currently estimated at ${deliveryPct}% of construction.`}
+            />
+          </span>
+          <span className="text-[0.72rem] font-medium text-gray-500">
+            {moneyFull(v.grossPerHome)}{" "}
+            <span className="text-gray-400">gross/home</span>
+          </span>
+        </div>
+        <div className="mt-1 text-[1.6rem] font-bold leading-none tabular-nums text-brandblue">
+          {moneyFull(v.netCost)}
+        </div>
+        <div className="mt-1.5 text-[0.72rem] text-gray-500">
+          {moneyFull(v.grossCost)} gross · {moneyFull(v.funding)} funding
+          secured
+        </div>
+      </div>
 
-      <GroupLabel>Annual benefits</GroupLabel>
-      <Row
-        label="Bill savings"
-        value={moneyFull(v.billSavings)}
-        note={`${moneyFull(v.billSavingsPerHome)}/home`}
-      />
-      <Row
-        label="Carbon saved"
-        value={`${Math.round(v.carbonSaved)} t`}
-        note={`≈ ${carsOffTheRoad(v.carbonSaved)} cars`}
-      />
+      {/* Cost breakdown — a proportion bar + rows keyed to it by colour. */}
+      <GroupLabel icon={Coins}>Cost breakdown</GroupLabel>
+      <div className="px-5">
+        <div className="mb-3 flex h-2 overflow-hidden rounded-full">
+          {costParts.map((p) => (
+            <span
+              key={p.label}
+              style={{
+                width: `${(p.value / grossForBar) * 100}%`,
+                background: p.color,
+              }}
+            />
+          ))}
+        </div>
+        {costParts.map((p) => (
+          <div
+            key={p.label}
+            className="flex items-center justify-between gap-3 py-1 text-[0.84rem]"
+          >
+            <span className="inline-flex items-center gap-2 text-gray-500">
+              <span
+                className="h-2 w-2 rounded-full"
+                style={{ background: p.color }}
+              />
+              {p.label}
+            </span>
+            <span className="tabular-nums font-semibold text-brandblue">
+              {moneyFull(p.value)}
+            </span>
+          </div>
+        ))}
+        <div className="mt-1 flex items-center justify-between gap-3 border-t border-gray-100 py-1 pt-2 text-[0.84rem]">
+          <span className="inline-flex items-center gap-2 text-gray-600">
+            <Landmark className="h-3.5 w-3.5 text-[#0c6b4a]" />
+            Funding secured
+          </span>
+          <span className="tabular-nums font-semibold text-[#0c6b4a]">
+            −{moneyFull(v.funding)}
+          </span>
+        </div>
+      </div>
 
-      <GroupLabel>Value for money</GroupLabel>
-      <Row label="Cost per SAP point" value={moneyFull(v.costPerSap)} />
-      <div className="pb-3">
-        <Row label="Cost per tCO₂/yr" value={moneyFull(v.costPerCarbon)} />
+      {/* Annual benefits — recurring, so tinted green like the savings they are. */}
+      <GroupLabel icon={Sprout}>Annual benefits</GroupLabel>
+      <div className="px-5">
+        <IconRow
+          icon={Banknote}
+          label="Bill savings"
+          value={moneyFull(v.billSavings)}
+          note={`${moneyFull(v.billSavingsPerHome)}/home`}
+          tone="benefit"
+        />
+        <IconRow
+          icon={Leaf}
+          label="Carbon saved"
+          value={`${Math.round(v.carbonSaved)} t`}
+          note={`≈ ${carsOffTheRoad(v.carbonSaved)} cars`}
+          tone="benefit"
+        />
+      </div>
+
+      {/* Value for money */}
+      <GroupLabel icon={Scale}>Value for money</GroupLabel>
+      <div className="px-5 pb-4">
+        <IconRow
+          icon={Gauge}
+          label="Cost per SAP point"
+          value={moneyFull(v.costPerSap)}
+        />
+        <IconRow
+          icon={Cloud}
+          label="Cost per tCO₂/yr"
+          value={moneyFull(v.costPerCarbon)}
+        />
       </div>
     </div>
   );