web: parity page renders the three-scenario comparison from live data

App.vue fetches the default config, posts it to /api/comparison, and
renders ComparisonTable; the Vite dev server proxies /api to the Go
server so the browser sees one origin. src/lib/api.ts is the only
fetch code and uses exclusively generated types: no shape is defined
on the frontend. Scaffold example components removed.
Engine fix surfaced by the smoke test: a nil Go slice marshals to
JSON null, violating the generated 'educated: number[]' contract;
RunScenario now returns an empty slice instead.
Verified end to end: curl through the Vite proxy returns the golden
99/70/7. Vitest covers the table rendering; type-check, oxlint,
eslint clean. This completes the milestone 2 parity check.

web/src/components/ComparisonTable.vue

@@ -0,0 +1,63 @@
+<script setup lang="ts">
+import type { ComparisonResponse } from '@/types/api'
+
+defineProps<{ comparison: ComparisonResponse }>()
+
+const strategyLabels: Record<string, string> = {
+  none: 'No program',
+  random: 'Educate at random',
+  'most-connected': 'Educate the most connected',
+}
+</script>
+
+<template>
+  <table>
+    <caption>
+      Same education budget ({{ comparison.config.numEducated }} of
+      {{ comparison.config.numStudents }} students), different targeting
+    </caption>
+    <thead>
+      <tr>
+        <th scope="col">Strategy</th>
+        <th scope="col">Educated</th>
+        <th scope="col">Reached</th>
+        <th scope="col">Share of school</th>
+        <th scope="col">Rounds</th>
+      </tr>
+    </thead>
+    <tbody>
+      <tr v-for="result in comparison.results" :key="result.strategy">
+        <th scope="row">{{ strategyLabels[result.strategy] ?? result.strategy }}</th>
+        <td>{{ result.educated.length }}</td>
+        <td>{{ result.numReached }} / {{ comparison.config.numStudents }}</td>
+        <td>{{ Math.round(result.reachedPct) }}%</td>
+        <td>{{ result.numRounds }}</td>
+      </tr>
+    </tbody>
+  </table>
+</template>
+
+<style scoped>
+table {
+  border-collapse: collapse;
+  margin-top: 1.5rem;
+}
+
+caption {
+  caption-side: top;
+  text-align: left;
+  padding-bottom: 0.75rem;
+  color: var(--color-text);
+}
+
+th,
+td {
+  border: 1px solid var(--color-border);
+  padding: 0.5rem 0.9rem;
+  text-align: left;
+}
+
+thead th {
+  background: var(--color-background-soft);
+}
+</style>