Complete phase two benchmarks, plot previews and static export workflow

frontend/src/services/functionPlotService.ts

@@ -0,0 +1,21 @@
+import { apiClient } from './apiClient'
+import DOMPurify from 'dompurify'
+
+interface PlotWire {
+  result: { content: string; width: number; height: number; warnings: string[] } | null
+  diagnostics: { message: string; severity: string; line?: number }[]
+  node_count: number
+}
+const cache = new Map<string, Promise<{ svg: string; warnings: string[]; nodeCount: number }>>()
+export function renderFunctionPlot(source: string, themeId = 'light') {
+  const key = JSON.stringify([source, themeId])
+  if (cache.has(key)) return cache.get(key)!
+  const result = apiClient.post<PlotWire>('/api/plots/function', { source, theme_id: themeId }, { timeoutMs: 30000 }).then(wire => ({
+    svg: DOMPurify.sanitize(wire.result?.content ?? '', { USE_PROFILES: { svg: true } }),
+    warnings: [...wire.diagnostics.map(d => `${d.message}${d.line ? ` (行 ${d.line})` : ''}`), ...(wire.result?.warnings ?? [])],
+    nodeCount: wire.node_count,
+  })).catch(error => { cache.delete(key); throw error })
+  if (cache.size >= 32) cache.delete(cache.keys().next().value!)
+  cache.set(key, result)
+  return result
+}