fix(cli): drain perf_hooks buffer to stop Ink dev-mode heap leak

Ink/react-reconciler in dev mode emits performance.mark/measure() on every
render. Without a PerformanceObserver, Node retains every entry in the User
Timing buffer forever — ~165 renders/sec in the TUI accumulate ~600MB of
PerformanceMeasure objects + diff strings ("Components ⚛", "Changed Props",
"– children", etc.) over 20-30min, which is what was OOM-crashing long dev
sessions. A 30s interval calling clearMeasures()/clearMarks() drains it.

Also teach scripts/dev-with-memory.mjs to forward --inspect /
--inspect-brk, plus auto-add --heapsnapshot-near-heap-limit=3 so any future
heap-limit OOM auto-dumps. The script now invokes node directly with tsx's
preflight + loader (resolved via require.resolve) instead of going through
the .bin/tsx wrapper, so the inspector attaches to the real app process
instead of a parent wrapper that exits before serving the websocket.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/cli/src/bin.ts

@@ -15,6 +15,7 @@ import { existsSync, mkdtempSync, readFileSync, symlinkSync, writeFileSync } fro
 import { createRequire } from "node:module";
 import { join, dirname } from "node:path";
 import { tmpdir } from "node:os";
+import { performance } from "node:perf_hooks";
 
 // @ts-expect-error -- Bun-only global; undefined in Node
 const isBunBinary = typeof Bun !== "undefined" && !!Bun.embeddedFiles;
@@ -59,6 +60,14 @@ function configurePiPackage(): void {
 
 configurePiPackage();
 
+// Drain Node's User Timing buffer. Ink (react-reconciler) in dev mode emits
+// performance.mark()/measure() on every render; entries accumulate forever
+// without an observer, retaining ~600MB after 20-30min of TUI rendering.
+setInterval(() => {
+  performance.clearMeasures();
+  performance.clearMarks();
+}, 30_000).unref();
+
 /**
  * Load `.env` (and `.env.local`) from the current working directory into
  * process.env so that secrets like FUSION_DAEMON_TOKEN can live in a local

scripts/dev-with-memory.mjs

@@ -53,28 +53,43 @@ const forwardedArgs = needsDevHostInjection
   ? [...args, "--host", "0.0.0.0"]
   : args;
 
+// Resolve absolute paths to tsx loader so they survive shell quoting.
+// Use Node's resolver instead of hardcoding the pnpm version-specific path.
+const { createRequire } = await import("node:module");
+const path = await import("node:path");
+const require = createRequire(import.meta.url);
+const tsxPkgJson = require.resolve("tsx/package.json");
+const tsxDir = path.dirname(tsxPkgJson);
+const PRELOAD = path.join(tsxDir, "dist", "preflight.cjs");
+const LOADER = path.join(tsxDir, "dist", "loader.mjs");
+const ENTRY = path.resolve(process.cwd(), "packages/cli/src/bin.ts");
+
+// Spawn node directly (no shell) so the inspector attaches to the real app
+// process and there's no parent/child wrapper consuming --inspect.
+function runApp(extraArgs) {
+  const tsx = spawn(process.execPath, [
+    "--require", PRELOAD,
+    "--import", `file://${LOADER}`,
+    ENTRY,
+    ...extraArgs,
+  ], {
+    stdio: "inherit",
+    env: { ...process.env, NODE_OPTIONS: runNodeOptions },
+  });
+  tsx.on("close", (c) => process.exit(c ?? 1));
+}
+
 // If no args, run default: build + CLI
 if (forwardedArgs.length === 0) {
   const pnpm = spawn("pnpm", ["build"], { stdio: "inherit", shell: true });
   pnpm.on("close", (code) => {
     if (code !== 0) process.exit(code ?? 1);
-    const tsx = spawn("node_modules/.bin/tsx", ["packages/cli/src/bin.ts"], {
+    runApp([]);
-      stdio: "inherit",
-      shell: true,
-      env: { ...process.env, NODE_OPTIONS: runNodeOptions },
-    });
-    tsx.on("close", (c) => process.exit(c ?? 1));
   });
 } else {
-  // Build first (without inspector), then exec the CLI with inspector flags.
   const build = spawn("pnpm", ["build"], { stdio: "inherit", shell: true });
   build.on("close", (code) => {
     if (code !== 0) process.exit(code ?? 1);
-    const tsx = spawn("node_modules/.bin/tsx", ["packages/cli/src/bin.ts", ...forwardedArgs], {
+    runApp(forwardedArgs);
-      stdio: "inherit",
-      shell: true,
-      env: { ...process.env, NODE_OPTIONS: runNodeOptions },
-    });
-    tsx.on("close", (c) => process.exit(c ?? 1));
   });
 }