feat(HAI-090): remove package.json dependency from compiled binary

- Inline version/name resolution in bin.ts so the binary works without package.json
- Simplify build.ts by removing package.json bundling steps
- Remove unused dynamic package.json lookups in engine merger, triage, and executor
- Expand build-exe tests to verify binary runs independently of package.json
- Clean up obsolete engine unit tests tied to removed package.json logic

packages/cli/build.ts

@@ -16,7 +16,7 @@
  */
 
 import { join, dirname } from "node:path";
-import { cpSync, mkdirSync, existsSync, rmSync, writeFileSync } from "node:fs";
+import { cpSync, mkdirSync, existsSync, rmSync } from "node:fs";
 
 const cliRoot = dirname(new URL(import.meta.url).pathname);
 const workspaceRoot = join(cliRoot, "..", "..");
@@ -102,14 +102,6 @@ function copyClientAssets() {
   console.log(`  → ${dashboardClientDest}`);
 }
 
-// ── Write a minimal package.json next to the binary ───────────────────
-function writeDistPackageJson() {
-  writeFileSync(
-    join(outDir, "package.json"),
-    JSON.stringify({ name: "hai", version: "0.1.0", type: "module" }, null, 2) + "\n",
-  );
-}
-
 // ── Compile a single binary ───────────────────────────────────────────
 function compileBinary(outFile: string, target: string): boolean {
   console.log(`Compiling ${outFile} (target: ${target})...`);
@@ -157,7 +149,6 @@ if (targets === null) {
   // Default: build for current platform → dist/hai
   const outBinary = join(outDir, defaultBinaryName());
   const ok = compileBinary(outBinary, "bun");
-  writeDistPackageJson();
   if (!ok) process.exit(1);
   console.log(`\n✓ Built: ${outBinary}`);
   console.log(`  Assets: ${dashboardClientDest}`);
@@ -178,8 +169,6 @@ if (targets === null) {
     }
   }
 
-  writeDistPackageJson();
-
   console.log(`\n${failed ? "⚠" : "✓"} Cross-compilation complete.`);
   if (built.length > 0) {
     console.log(`  Built ${built.length} binaries:`);

packages/cli/src/__tests__/build-exe.test.ts

@@ -1,14 +1,30 @@
 import { describe, it, expect, beforeAll } from "vitest";
 import { execSync, spawnSync } from "node:child_process";
-import { existsSync } from "node:fs";
+import { cpSync, existsSync } from "node:fs";
 import { join } from "node:path";
 import { mkdtempSync, rmSync } from "node:fs";
 import { tmpdir } from "node:os";
 
 const cliRoot = join(import.meta.dirname!, "..", "..");
 const outBinary = join(cliRoot, "dist", process.platform === "win32" ? "hai.exe" : "hai");
+const binaryName = process.platform === "win32" ? "hai.exe" : "hai";
 const clientDir = join(cliRoot, "dist", "client");
 
+/**
+ * Create an isolated temp directory containing only the binary and client/
+ * assets — no package.json. Returns the dir path and a cleanup function.
+ */
+function createIsolatedDir(): { dir: string; binary: string; cleanup: () => void } {
+  const dir = mkdtempSync(join(tmpdir(), "hai-iso-"));
+  cpSync(outBinary, join(dir, binaryName), { recursive: true });
+  cpSync(clientDir, join(dir, "client"), { recursive: true });
+  return {
+    dir,
+    binary: join(dir, binaryName),
+    cleanup: () => rmSync(dir, { recursive: true, force: true }),
+  };
+}
+
 describe("build-exe", () => {
   beforeAll(() => {
     // Build the executable (skip if already built to speed up re-runs)
@@ -29,41 +45,52 @@ describe("build-exe", () => {
     expect(existsSync(join(clientDir, "index.html"))).toBe(true);
   });
 
-  it("binary runs --help and prints expected output", () => {
-    const result = spawnSync(outBinary, ["--help"], {
-      encoding: "utf-8",
-      timeout: 15_000,
-    });
-    expect(result.status).toBe(0);
-    expect(result.stdout).toContain("hai — AI-orchestrated task board");
-    expect(result.stdout).toContain("dashboard");
-    expect(result.stdout).toContain("task create");
-    expect(result.stdout).toContain("task list");
+  it("dist/ does not contain a package.json", () => {
+    expect(existsSync(join(cliRoot, "dist", "package.json"))).toBe(false);
+  });
+
+  it("binary runs --help without a co-located package.json", () => {
+    const { binary, dir, cleanup } = createIsolatedDir();
+    try {
+      // Verify no package.json in the isolated dir
+      expect(existsSync(join(dir, "package.json"))).toBe(false);
+
+      const result = spawnSync(binary, ["--help"], {
+        encoding: "utf-8",
+        timeout: 15_000,
+      });
+      expect(result.status).toBe(0);
+      expect(result.stdout).toContain("hai — AI-orchestrated task board");
+      expect(result.stdout).toContain("dashboard");
+      expect(result.stdout).toContain("task create");
+      expect(result.stdout).toContain("task list");
+    } finally {
+      cleanup();
+    }
   });
 
   it("binary runs 'task list' without crashing", () => {
-    const tmpDir = mkdtempSync(join(tmpdir(), "hai-test-"));
+    const { binary, cleanup } = createIsolatedDir();
     try {
-      const result = spawnSync(outBinary, ["task", "list"], {
-        cwd: tmpDir,
+      const result = spawnSync(binary, ["task", "list"], {
         encoding: "utf-8",
         timeout: 15_000,
       });
       expect(result.status).toBe(0);
       expect(result.stdout).toContain("No tasks yet");
     } finally {
-      rmSync(tmpDir, { recursive: true, force: true });
+      cleanup();
     }
   });
 
   it("binary starts dashboard and serves client assets", async () => {
     const { spawn } = await import("node:child_process");
-    const tmpDir = mkdtempSync(join(tmpdir(), "hai-dash-test-"));
+    const { binary, dir, cleanup } = createIsolatedDir();
     const port = 14040 + Math.floor(Math.random() * 1000);
     try {
       const output = await new Promise<string>((resolve, reject) => {
-        const child = spawn(outBinary, ["dashboard", "--no-open", "-p", String(port)], {
-          cwd: tmpDir,
+        const child = spawn(binary, ["dashboard", "--no-open", "-p", String(port)], {
+          cwd: dir,
           stdio: ["ignore", "pipe", "pipe"],
         });
         let out = "";
@@ -85,7 +112,7 @@ describe("build-exe", () => {
       });
       expect(output).toContain("hai board");
     } finally {
-      rmSync(tmpDir, { recursive: true, force: true });
+      cleanup();
     }
   }, 15_000);
 });

packages/cli/src/bin.ts

@@ -1,7 +1,45 @@
 #!/usr/bin/env node
 
-import { runDashboard } from "./commands/dashboard.js";
-import { runTaskCreate, runTaskList, runTaskMove, runTaskMerge, runTaskUpdate, runTaskLog, runTaskShow, runTaskAttach } from "./commands/task.js";
+/**
+ * Bootstrap: when running as a bun-compiled binary, the bundled pi-coding-agent
+ * reads package.json from the executable's directory at module-init time
+ * (top-level `readFileSync` in its config module). We redirect that read to a
+ * temp directory containing a minimal package.json so the binary works
+ * standalone without any co-located package.json.
+ *
+ * Node built-ins are safe to import statically — they have no side-effects
+ * that depend on package.json. All application imports MUST be dynamic
+ * (after the env is configured) so they resolve after PI_PACKAGE_DIR is set.
+ */
+import { mkdtempSync, writeFileSync, existsSync } from "node:fs";
+import { join, dirname } from "node:path";
+import { tmpdir } from "node:os";
+
+// @ts-expect-error -- Bun-only global; undefined in Node
+const isBunBinary = typeof Bun !== "undefined" && !!Bun.embeddedFiles;
+
+if (isBunBinary) {
+  const execDir = dirname(process.execPath);
+  const localPkg = join(execDir, "package.json");
+
+  if (!existsSync(localPkg)) {
+    // Write a minimal package.json to a temp dir and redirect PI_PACKAGE_DIR
+    const tmp = mkdtempSync(join(tmpdir(), "hai-pkg-"));
+    writeFileSync(
+      join(tmp, "package.json"),
+      JSON.stringify(
+        { name: "hai", version: "0.1.0", type: "module", piConfig: { name: "hai", configDir: ".hai" } },
+        null,
+        2,
+      ) + "\n",
+    );
+    process.env.PI_PACKAGE_DIR = tmp;
+  }
+}
+
+// Dynamic imports so the pi-coding-agent config module sees PI_PACKAGE_DIR
+const { runDashboard } = await import("./commands/dashboard.js");
+const { runTaskCreate, runTaskList, runTaskMove, runTaskMerge, runTaskUpdate, runTaskLog, runTaskShow, runTaskAttach } = await import("./commands/task.js");
 
 const HELP = `
 hai — AI-orchestrated task board