B4: design --version prints the version, and the probe uses it

The design CLI treated --version as an unknown command (exit 1), so the
probe launched the binary with no arguments instead. Add --version (prints
the gstack version, exit 0, before auth or network) and probe with it, so
messages read '<path> --version exited <code>' as planned.

design/src/cli.ts

@@ -26,6 +26,7 @@ import { generateDesignToCodePrompt } from "./design-to-code";
 import { serve } from "./serve";
 import { gallery } from "./gallery";
 import { normalizeIntFlag } from "./flag-utils";
+import { readVersionString } from "./daemon-state";
 import {
   daemonStatus as daemonStatusClient,
   ensureDaemon,
@@ -44,6 +45,11 @@ function parseArgs(argv: string[]): {
     printUsage();
     process.exit(0);
   }
+  // DESIGN SETUP's launch probe (B4): proves the binary starts, without auth or network.
+  if (args[0] === "--version") {
+    console.log(readVersionString());
+    process.exit(0);
+  }
 
   const command = args[0];
   const flags: Record<string, string | boolean> = {};

design/test/cli-version.test.ts

@@ -0,0 +1,21 @@
+/**
+ * B4: DESIGN SETUP probes `"$D" --version` to prove the binary starts. The CLI
+ * treated `--version` as an unknown command (exit 1), so the probe could never
+ * pass. It prints the gstack version and exits 0, before auth or network.
+ */
+import { describe, expect, test } from 'bun:test';
+import { spawnSync } from 'child_process';
+import * as fs from 'fs';
+import * as path from 'path';
+
+const ROOT = path.resolve(import.meta.dir, '..', '..');
+
+describe('design --version', () => {
+  test('prints the gstack version and exits 0 without credentials', () => {
+    const r = spawnSync(process.execPath, [path.join(ROOT, 'design/src/cli.ts'), '--version'], {
+      encoding: 'utf8', timeout: 30_000, env: { PATH: process.env.PATH ?? '', HOME: '/nonexistent' },
+    });
+    expect(r.status, r.stderr).toBe(0);
+    expect(r.stdout.trim()).toBe(fs.readFileSync(path.join(ROOT, 'VERSION'), 'utf8').trim());
+  });
+});

scripts/resolvers/design.ts

@@ -1118,8 +1118,8 @@ Source: [OpenAI "Designing Delightful Frontends with GPT-5.4"](https://developer
 /**
  * B4 (#1076, #1254): DESIGN_READY only when the binary actually starts. A
  * binary that is merely executable can still be SIGKILLed at launch (an
- * invalid macOS code signature), so launch it (no arguments prints usage and
- * exits 0) under the portable deadline aside.ts uses. A success is cached
+ * invalid macOS code signature), so run `--version` under the portable
+ * deadline aside.ts uses. A success is cached
  * (inode + path, valid while newer than the binary) so Gatekeeper's
  * first-launch scan is paid once.
  */
@@ -1129,15 +1129,15 @@ _dt() { if command -v gtimeout >/dev/null; then gtimeout 10 "$@"; elif command -
 elif command -v perl >/dev/null; then perl -e 'alarm(shift);exec(@ARGV)' 10 "$@"; else return 125; fi; }
 _RC=0; _F="Fix: cd \${D%/design/dist/design} && ./setup"
 if [ ! -x "$D" ]; then _RC=missing
-elif [ ! "$_DC" -nt "$D" ] || [ "$(cat "$_DC")" != "$_DK" ]; then _dt "$D" >/dev/null 2>&1 </dev/null || _RC=$?
+elif [ ! "$_DC" -nt "$D" ] || [ "$(cat "$_DC")" != "$_DK" ]; then _dt "$D" --version >/dev/null 2>&1 </dev/null || _RC=$?
 fi
 case "$_RC" in
   0) echo "DESIGN_READY: $D"; [ -n "$_DC" ] && echo "$_DK" > "$_DC" 2>/dev/null ;;
   missing) echo "DESIGN_NOT_AVAILABLE: $D is not installed. $_F" ;;
-  124|142) echo "DESIGN_NOT_AVAILABLE: $D timed out after 10s" ;;
+  124|142) echo "DESIGN_NOT_AVAILABLE: $D --version timed out after 10s" ;;
   125) echo "DESIGN_NOT_AVAILABLE: no timeout/gtimeout/perl to bound $D" ;;
-  137) echo "DESIGN_NOT_AVAILABLE: $D exited 137 (killed at launch; on macOS usually an invalid code signature). $_F" ;;
-  *) echo "DESIGN_NOT_AVAILABLE: $D exited $_RC" ;;
+  137) echo "DESIGN_NOT_AVAILABLE: $D --version exited 137 (killed at launch; on macOS usually an invalid code signature). $_F" ;;
+  *) echo "DESIGN_NOT_AVAILABLE: $D --version exited $_RC" ;;
 esac`;
 }
 
@@ -1421,7 +1421,7 @@ else
 fi
 \`\`\`
 
-**If TASTE_PROFILE_UNAVAILABLE:** say that line once, then continue without a taste profile (do not treat it as "no history").
+**If TASTE_PROFILE_UNAVAILABLE:** say so once; continue without a taste profile.
 
 **If TASTE_PROFILE_FOUND:** Parse the full JSON; malformed/unreadable uses the legacy fallback. After decay, rank each dimension by confidence * approved_count (or rejected_count); take three per kind. Count retained sessions (at most 50, not lifetime). Include in ${ctx.skillName === 'design-consultation' ? 'the Phase 1 product brief (later shared unchanged with both independent voices)' : 'the brief'}:
 

test/design-setup-probe.test.ts

@@ -61,13 +61,13 @@ describe('B4: DESIGN_READY requires a binary that starts', () => {
       expect(w.launches()).toBe(1);
       fs.writeFileSync(path.join(w.install, 'design/dist/design'), `#!/bin/sh\necho launched >> "${w.home}/launches"\nexit 3\n`);
       fs.utimesSync(path.join(w.install, 'design/dist/design'), new Date(), new Date(Date.now() + 5_000));
-      expect(run(setup(), w).stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design exited 3`);
+      expect(run(setup(), w).stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design --version exited 3`);
     });
 
     test(`${host.name}: a binary killed at launch is not ready and names the fix`, () => {
       const w = world(host.root, 'kill -9 $$');
       const r = run(setup(), w);
-      expect(r.stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design exited 137 (killed at launch; on macOS usually an invalid code signature). Fix: cd ${w.install} && ./setup`);
+      expect(r.stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design --version exited 137 (killed at launch; on macOS usually an invalid code signature). Fix: cd ${w.install} && ./setup`);
       expect(fs.existsSync(path.join(w.state, 'design-ready'))).toBe(false);
     });
 
@@ -100,7 +100,7 @@ describe('B4: DESIGN_READY requires a binary that starts', () => {
       child.on('error', reject);
       child.on('close', () => resolve(text));
     });
-    expect(stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design timed out after 10s`);
+    expect(stdout.trim()).toBe(`DESIGN_NOT_AVAILABLE: ${w.install}/design/dist/design --version timed out after 10s`);
   }, 30_000);
 
   test('office-hours visual exploration uses the same probe', () => {