Add mass driver station system with Lagrange point placement

- Lagrange point computation (L1-L5) for any Sun-planet pair in Rust
- Station generation: auto-place at Lagrange points by priority (inner → outer planets)
- Station panel UI: count slider (5-50), launch velocity slider (5-100 km/s) with info tooltip
- Blue diamond markers on 2D canvas with labels when zoomed in
- Active station list in sidebar (Earth L1, Mars L2, Jupiter L4, etc.)
- WASM API: generate_stations(), get_station_positions(), get_station_names()
- Station positions update every frame (co-rotating with planets at Lagrange points)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/routes/+page.svelte

@@ -6,6 +6,7 @@
 	import Viewport from './(simulator)/components/Viewport.svelte';
 	import TimeControls from './(simulator)/components/TimeControls.svelte';
 	import ViewToggle from './(simulator)/components/ViewToggle.svelte';
+	import StationPanel from './(simulator)/components/StationPanel.svelte';
 
 	let wasmError = $state('');
 
@@ -14,7 +15,6 @@
 			await initWasm();
 			simulation.bodyInfos = getBodyInfos();
 			simulation.wasmReady = true;
-			// Start in Jan 2025 for a recognizable view
 			simulation.setDate(2025, 1, 1);
 			simulation.isPlaying = true;
 		} catch (e) {
@@ -37,23 +37,30 @@
 	</header>
 
 	<!-- Main content -->
-	<main class="flex-1 relative overflow-hidden">
+	<main class="flex-1 flex overflow-hidden">
 		{#if wasmError}
-			<div class="absolute inset-0 flex items-center justify-center">
+			<div class="flex-1 flex items-center justify-center">
 				<div class="bg-red-900/50 border border-red-500/30 rounded-lg p-6 max-w-md">
 					<h2 class="text-red-400 font-bold mb-2">Failed to load simulation engine</h2>
 					<p class="text-sm text-red-300/80">{wasmError}</p>
 				</div>
 			</div>
 		{:else if !simulation.wasmReady}
-			<div class="absolute inset-0 flex items-center justify-center">
+			<div class="flex-1 flex items-center justify-center">
 				<div class="text-center">
 					<div class="w-8 h-8 border-2 border-[var(--accent-blue)] border-t-transparent rounded-full animate-spin mx-auto mb-3"></div>
 					<p class="text-sm text-[var(--text-secondary)]">Initializing simulation engine...</p>
 				</div>
 			</div>
 		{:else}
-			<Viewport />
+			<!-- Viewport -->
+			<div class="flex-1 relative">
+				<Viewport />
+			</div>
+			<!-- Right sidebar -->
+			<aside class="w-64 shrink-0 p-2 bg-[var(--bg-secondary)] border-l border-white/5 overflow-y-auto">
+				<StationPanel />
+			</aside>
 		{/if}
 	</main>