perf(desktop): remember the bundled CLI version between launches

Every launch spawned the bundled 200 MB CLI executable for --version and
waited ~380 ms for it before the background service, WSL support and,
because windows are created after every layer builds, the window itself.
The version only changes when an update replaces the executable, so keep
it in the settings store keyed by the executable's path, size and mtime
and only spawn when that identity changes.

Packaged build, warm service, 5 launches (median ms since spawn):
renderer process 851 -> 512, window visible 1085 -> 778,
shell visible 1289 -> 961.

packages/desktop/src/main/service/desktop-cli.ts

@@ -3,9 +3,11 @@ export * as DesktopCli from "./desktop-cli"
 import { execFile, spawn } from "node:child_process"
 import { promisify } from "node:util"
 import { app } from "electron"
-import { Context, Effect, FileSystem, Layer, Path } from "effect"
+import { Context, Effect, FileSystem, Layer, Option, Path } from "effect"
 import installer from "../../../../../install?raw"
 import { DesktopPaths } from "../paths"
+import { BUNDLED_CLI_VERSION_KEY } from "../storage/keys"
+import { getStore } from "../storage/store"
 import { parseCliVersion } from "./cli-version"
 
 const execFileAsync = promisify(execFile)
@@ -79,11 +81,36 @@ const resolveBundledCli = Effect.fn("DesktopCli.resolveBundled")(function* (isol
     ? path.join(process.resourcesPath, executableName())
     : path.join(paths.developmentResourcesRoot, isolated ? developmentExecutableName() : executableName())
   yield* Effect.logInfo("v2 CLI executable resolved", { bundled, packaged: app.isPackaged })
-  const version = parseCliVersion(yield* run(bundled, ["--version"]))
+  const version = yield* bundledVersion(bundled)
   const binary = app.isPackaged || isolated ? yield* installCli(bundled, version) : bundled
   return { version, binary, command: [binary] }
 })
 
+// Spawning the bundled executable for `--version` costs ~400 ms of startup on a 200 MB binary, so
+// the answer is remembered per executable identity and only re-read after an update replaces it.
+const bundledVersion = Effect.fn("DesktopCli.bundledVersion")(function* (bundled: string) {
+  const fs = yield* FileSystem.FileSystem
+  const stat = yield* fs.stat(bundled).pipe(Effect.orElseSucceed(() => undefined))
+  const identity = stat ? `${stat.size}:${Option.getOrUndefined(stat.mtime)?.getTime() ?? ""}` : undefined
+  const store = getStore()
+  const cached = store.get(BUNDLED_CLI_VERSION_KEY)
+  if (identity && isVersionCache(cached) && cached.path === bundled && cached.identity === identity) {
+    yield* Effect.logInfo("v2 CLI version reused", { version: cached.version })
+    return cached.version
+  }
+  const version = parseCliVersion(yield* run(bundled, ["--version"]))
+  if (identity) store.set(BUNDLED_CLI_VERSION_KEY, { path: bundled, identity, version } satisfies VersionCache)
+  return version
+})
+
+type VersionCache = { path: string; identity: string; version: string }
+
+function isVersionCache(value: unknown): value is VersionCache {
+  if (!value || typeof value !== "object") return false
+  const cache = value as Record<string, unknown>
+  return typeof cache.path === "string" && typeof cache.identity === "string" && typeof cache.version === "string"
+}
+
 export const cleanStages = Effect.fn("DesktopCli.cleanStages")(function* (binary: string) {
   const fs = yield* FileSystem.FileSystem
   const path = yield* Path.Path

packages/desktop/src/main/storage/keys.ts

@@ -5,3 +5,4 @@ export const WSL_SERVERS_KEY = "wslServers"
 export const PINCH_ZOOM_ENABLED_KEY = "pinchZoomEnabled"
 export const BACKGROUND_COLOR_KEY = "backgroundColor"
 export const WINDOW_IDS_KEY = "windowIds"
+export const BUNDLED_CLI_VERSION_KEY = "bundledCliVersion"

packages/desktop/src/main/windows/protocol.ts

@@ -17,8 +17,6 @@ protocol.registerSchemesAsPrivileged([
       standard: true,
       supportFetchAPI: true,
       stream: true,
-      // Let Chromium keep V8 bytecode for the renderer bundle between launches.
-      codeCache: true,
     },
   },
 ])