perf(browser): isolate profile hot-reload config refresh

src/browser/resolved-config-refresh.ts

@@ -0,0 +1,58 @@
+import type { BrowserServerState } from "./server-context.types.js";
+import { createConfigIO, loadConfig } from "../config/config.js";
+import { resolveBrowserConfig, resolveProfile, type ResolvedBrowserProfile } from "./config.js";
+
+function applyResolvedConfig(
+  current: BrowserServerState,
+  freshResolved: BrowserServerState["resolved"],
+) {
+  current.resolved = freshResolved;
+  for (const [name, runtime] of current.profiles) {
+    const nextProfile = resolveProfile(freshResolved, name);
+    if (nextProfile) {
+      runtime.profile = nextProfile;
+      continue;
+    }
+    if (!runtime.running) {
+      current.profiles.delete(name);
+    }
+  }
+}
+
+export function refreshResolvedBrowserConfigFromDisk(params: {
+  current: BrowserServerState;
+  refreshConfigFromDisk: boolean;
+  mode: "cached" | "fresh";
+}) {
+  if (!params.refreshConfigFromDisk) {
+    return;
+  }
+  const cfg = params.mode === "fresh" ? createConfigIO().loadConfig() : loadConfig();
+  const freshResolved = resolveBrowserConfig(cfg.browser, cfg);
+  applyResolvedConfig(params.current, freshResolved);
+}
+
+export function resolveBrowserProfileWithHotReload(params: {
+  current: BrowserServerState;
+  refreshConfigFromDisk: boolean;
+  name: string;
+}): ResolvedBrowserProfile | null {
+  refreshResolvedBrowserConfigFromDisk({
+    current: params.current,
+    refreshConfigFromDisk: params.refreshConfigFromDisk,
+    mode: "cached",
+  });
+  let profile = resolveProfile(params.current.resolved, params.name);
+  if (profile) {
+    return profile;
+  }
+
+  // Hot-reload: profile missing; retry with a fresh disk read without flushing the global cache.
+  refreshResolvedBrowserConfigFromDisk({
+    current: params.current,
+    refreshConfigFromDisk: params.refreshConfigFromDisk,
+    mode: "fresh",
+  });
+  profile = resolveProfile(params.current.resolved, params.name);
+  return profile;
+}