perf(dashboard): 仪表盘加载提速

- models-dev 快照移出主 bundle（1.35MB→515KB），改为 /models-dev.json 运行时异步加载，就绪后重渲染
- Rust 启动时后台预热价格索引（warm_price_index），首次 get_summary 不再卡
- get_summary 扫描结果 8s TTL 缓存（按 home），切 tab/改范围复用；刷新按钮 refresh=true 强制重扫

src-tauri/src/dashboard.rs

@@ -530,6 +530,15 @@ fn models_dev_cost_index() -> &'static HashMap<String, ModelsDevCost> {
     })
 }
 
+/// Warm the compiled-in models.dev price index off the first dashboard open:
+/// parsing the ~1.3 MB snapshot costs tens of milliseconds, so build it on a
+/// background thread at startup instead of lazily on the first get_summary.
+pub fn warm_price_index() {
+    std::thread::spawn(|| {
+        let _ = models_dev_cost_index();
+    });
+}
+
 /// Official providers take precedence over resellers when the same model id
 /// ships under multiple providers and no provider prefix disambiguates.
 const OFFICIAL_PROVIDERS: &[&str] = &[
@@ -743,6 +752,45 @@ fn scan_usage(home: &Path) -> (Vec<UsageRecord>, ScanMeta) {
     })
 }
 
+// ---------------------------------------------------------------------------
+// Scan cache
+// ---------------------------------------------------------------------------
+
+/// Short-TTL cache for the expensive `scan_usage` walk (reads every
+/// wire.jsonl under the sessions root and prices every record). Tab switches
+/// call get_summary repeatedly; re-walking the whole tree on every switch is
+/// the main dashboard lag. Keyed by home, expires after 8s; `refresh=true`
+/// bypasses it.
+struct SummaryCacheEntry {
+    home: String,
+    scanned_at: std::time::Instant,
+    records: Vec<UsageRecord>,
+    meta: ScanMeta,
+}
+
+static SUMMARY_CACHE: Mutex<Option<SummaryCacheEntry>> = Mutex::new(None);
+const SUMMARY_CACHE_TTL: std::time::Duration = std::time::Duration::from_secs(8);
+
+fn scan_usage_cached(home: &Path, refresh: bool) -> (Vec<UsageRecord>, ScanMeta) {
+    let home_s = home.to_string_lossy().to_string();
+    let mut cache = SUMMARY_CACHE.lock().unwrap();
+    let hit = cache
+        .as_ref()
+        .is_some_and(|e| !refresh && e.home == home_s && e.scanned_at.elapsed() < SUMMARY_CACHE_TTL);
+    if hit {
+        let e = cache.as_ref().unwrap();
+        return (e.records.clone(), e.meta.clone());
+    }
+    let (records, meta) = scan_usage(home);
+    *cache = Some(SummaryCacheEntry {
+        home: home_s,
+        scanned_at: std::time::Instant::now(),
+        records: records.clone(),
+        meta: meta.clone(),
+    });
+    (records, meta)
+}
+
 // ---------------------------------------------------------------------------
 // Aggregate
 // ---------------------------------------------------------------------------
@@ -1489,13 +1537,13 @@ pub fn get_prices() -> PricesResult {
 
 #[tauri::command]
 pub fn get_summary(home_override: Option<String>, range: Option<String>, refresh: Option<bool>) -> SummaryResult {
-    let _refresh = refresh.unwrap_or(false);
+    let refresh = refresh.unwrap_or(false);
     let home = resolve_kimi_home(home_override);
     let now_ms = std::time::SystemTime::now()
         .duration_since(std::time::UNIX_EPOCH).unwrap_or_default().as_millis() as u64;
     let r = range.unwrap_or_else(|| "30d".into());
 
-    let (records, meta) = scan_usage(&home);
+    let (records, meta) = scan_usage_cached(&home, refresh);
     let stats = aggregate(&records, &r, now_ms);
     let all_stats = aggregate(&records, "all", now_ms);
     let heatmap = build_heatmap(&records, now_ms);

src-tauri/src/lib.rs

@@ -27,6 +27,8 @@ pub fn run() {
         .plugin(tauri_plugin_opener::init())
         .setup(|app| {
             println!("[Tauri] Setup started");
+            // Build the models.dev price index off the first dashboard query.
+            dashboard::warm_price_index();
             let window = app.get_webview_window("main").unwrap();
             println!("[Tauri] Window label: {}", window.label());
 

src/App.tsx

@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useMemo, useState } from "react";
+import { useCallback, useEffect, useMemo, useReducer, useState } from "react";
 import { invoke } from "@tauri-apps/api/core";
 import { getCurrentWindow } from "@tauri-apps/api/window";
 import { useConfig } from "./hooks/useConfig";
@@ -12,7 +12,7 @@ import { UsageConfigModal } from "./components/UsageConfigModal";
 import { PresetPickerModal } from "./components/PresetPickerModal";
 import { useTranslation } from "./i18n";
 import { getDefaultMaxContextSize } from "./lib/model-defaults";
-import { getModelRef } from "./lib/models-dev";
+import { getModelRef, modelsDevReady, onModelsDevReady } from "./lib/models-dev";
 import {
   presetToProviderAndModels,
   type ProviderPreset,
@@ -121,6 +121,14 @@ export default function App() {
     }).catch(() => {});
   }, [loading, config, agent]);
 
+  // Load the models.dev index in the background (not in the main bundle)
+  // and re-render once it lands so context/capability columns fill in.
+  const [, forceModelsDevReady] = useReducer((x: number) => x + 1, 0);
+  useEffect(() => {
+    onModelsDevReady(forceModelsDevReady);
+    void modelsDevReady();
+  }, []);
+
   const providers = useMemo(
     () => (config ? Object.values(config.providers) : []),
     [config]

src/components/dashboard/DashboardPage.tsx

@@ -71,7 +71,7 @@ export function DashboardPage() {
           <div className="text-red-400 mb-2">{t("dashLoadFailed")}</div>
           <div className="text-sm text-content-muted">{error}</div>
           <button
-            onClick={() => refresh()}
+            onClick={() => refresh(true)}
             className="mt-4 px-4 py-2 rounded bg-blue-600 hover:bg-blue-700 text-white text-sm"
           >
             {t("retry")}
@@ -145,7 +145,7 @@ export function DashboardPage() {
         </div>
         <button
           type="button"
-          onClick={() => refresh()}
+          onClick={() => refresh(true)}
           disabled={loading}
           className="px-3 py-1.5 text-sm border border-border rounded hover:bg-hover-2 text-content-muted hover:text-content-primary disabled:opacity-50"
         >

src/hooks/useDashboard.ts

@@ -23,11 +23,14 @@ export function useDashboard() {
   const [loading, setLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
 
-  const refresh = useCallback(async () => {
+  const refresh = useCallback(async (force = false) => {
     setLoading(true);
     setError(null);
     try {
-      const result = await invoke<SummaryResult>("get_summary", { range });
+      const result = await invoke<SummaryResult>("get_summary", {
+        range,
+        refresh: force,
+      });
       setData(result);
     } catch (err) {
       const msg = err instanceof Error ? err.message : String(err);

src/lib/models-dev.ts

@@ -1,9 +1,15 @@
-import snapshot from "./models-dev.json";
-
 /**
  * Compact per-model reference data from models.dev
  * (see scripts/fetch-models-dev.mjs).
+ *
+ * The snapshot (~1.3 MB JSON) is NOT bundled into the main chunk anymore:
+ * parsing a 1.3 MB JSON literal at startup blocks first paint. It is served
+ * as a static asset (`/models-dev.json`) and loaded once in the background.
+ * `getModelRef` stays synchronous and returns undefined until the index is
+ * ready — callers already fall back to defaults — and `modelsDevReady()`
+ * lets the app re-render once the index arrives.
  */
+
 export interface ModelCost {
   input?: number;
   output?: number;
@@ -23,22 +29,58 @@ export interface ModelRef {
   cost?: ModelCost;
 }
 
-const raw = snapshot as Record<string, unknown>;
+let byLowerKey: Record<string, ModelRef> | null = null;
+let readyListeners: Array<() => void> = [];
 
-// Drop the "last_updated" metadata key; the rest is "<provider>/<model>".
-const data: Record<string, ModelRef> = {};
-for (const [key, value] of Object.entries(raw)) {
-  if (key !== "last_updated" && value && typeof value === "object") {
-    data[key] = value as ModelRef;
+function buildIndex(raw: Record<string, unknown>) {
+  const data: Record<string, ModelRef> = {};
+  for (const [key, value] of Object.entries(raw)) {
+    if (key !== "last_updated" && value && typeof value === "object") {
+      data[key] = value as ModelRef;
+    }
   }
+  // models.dev keys are "<lab>/<model>" and may be mixed-case (e.g.
+  // "minimax/MiniMax-M3"), while provider APIs return bare model ids
+  // (e.g. "kimi-k2.5"). Index lowercase for tolerant matching.
+  const lower: Record<string, ModelRef> = {};
+  for (const [key, value] of Object.entries(data)) {
+    lower[key.toLowerCase()] = value;
+  }
+  return lower;
 }
 
-// models.dev keys are "<lab>/<model>" and may be mixed-case (e.g.
-// "minimax/MiniMax-M3"), while provider APIs return bare model ids
-// (e.g. "kimi-k2.5"). Index lowercase for tolerant matching.
-const byLowerKey: Record<string, ModelRef> = {};
-for (const [key, value] of Object.entries(data)) {
-  byLowerKey[key.toLowerCase()] = value;
+let loadPromise: Promise<void> | null = null;
+
+export function modelsDevReady(): Promise<void> {
+  if (!loadPromise) {
+    loadPromise = fetch(`${import.meta.env.BASE_URL}models-dev.json`)
+      .then((r) => {
+        if (!r.ok) throw new Error(`models-dev.json HTTP ${r.status}`);
+        return r.json() as Promise<Record<string, unknown>>;
+      })
+      .then((raw) => {
+        byLowerKey = buildIndex(raw);
+        const listeners = readyListeners;
+        readyListeners = [];
+        for (const cb of listeners) cb();
+      })
+      .catch((err) => {
+        // A failed load is permanent for this session: fall back to defaults.
+        byLowerKey = {};
+        loadPromise = null; // allow one retry next time
+        console.warn("models-dev.json load failed:", err);
+      });
+  }
+  return loadPromise;
+}
+
+/** Register a callback invoked once the models.dev index is ready. */
+export function onModelsDevReady(cb: () => void): void {
+  if (byLowerKey) {
+    cb();
+    return;
+  }
+  readyListeners.push(cb);
 }
 
 /**
@@ -49,7 +91,7 @@ for (const [key, value] of Object.entries(data)) {
  */
 export function getModelRef(modelId: string): ModelRef | undefined {
   const id = modelId.trim().toLowerCase();
-  if (!id) return undefined;
+  if (!id || !byLowerKey) return undefined;
   const exact = byLowerKey[id];
   if (exact) return exact;
   const suffix = `/${id}`;