feat: click expected value + contribution display

CockpitHeader: /clic shows expected value (double+crit included), amber.
ClickPanel: full breakdown with expected value, contribution estimate
(~5 clics/s → X/s + auto → Y% of total), formula visible.
Passif/clic distinction clear in the cockpit.

Frontend/src/lib/components/CockpitHeader.svelte

@@ -1,17 +1,22 @@
 <script lang="ts">
 	import { game } from '$lib/stores/game.svelte';
+	import { getClickBreakdown } from '$lib/core/economy';
 	import { formatNumber } from '$lib/utils/formatNumber';
+
+	let cb = $derived(getClickBreakdown(game.state));
+	// Expected value per click = total × (1 + doubleChance + critChance × 9)
+	let expectedPerClick = $derived(cb.total * (1 + cb.doubleChance + cb.critChance * 9));
 </script>
 
 <div class="gp">
 	<div class="grid grid-cols-5 gap-0.5 px-1">
-		<div class="gp-stat" title="Production automatique par seconde">
-			<span class="gp-label">Prod/s</span>
-			<span class="gp-value gp-accent-green text-[0.8rem]!">{formatNumber(game.productionPerSecond)}</span>
+		<div class="gp-stat" title="Production passive par seconde (generateurs)">
+			<span class="gp-label">Passif</span>
+			<span class="gp-value gp-accent-green text-[0.8rem]!">{formatNumber(game.productionPerSecond)}/s</span>
 		</div>
-		<div class="gp-stat" title="Tetards gagnes par clic">
+		<div class="gp-stat" title="Valeur attendue par clic (double + crit inclus)">
 			<span class="gp-label">/clic</span>
-			<span class="gp-value text-[0.8rem]!">{formatNumber(game.clickGain)}</span>
+			<span class="gp-value gp-accent-amber text-[0.8rem]!">{formatNumber(expectedPerClick)}</span>
 		</div>
 		<div class="gp-stat" title="Multiplicateur global (prestige)">
 			<span class="gp-label">Mult</span>