onboard-driver: scrub secrets from signin output passthrough

- Redact identifier/code (>=4 chars) from muse-signin.py stdout/stderr before passthrough (it echoes OTP input).

- Catch TimeoutExpired: its str() includes argv with --email/--otp; print generic timeout instead.

- Log email_masked instead of raw email to job-log.jsonl (rc=4 branch).

bin/onboard-driver.py

@@ -29,6 +29,19 @@ import urllib.request
 SIGNIN = "/home/super/Projects/NetVM/bin/muse-signin.py"
 
 
+def _scrub(text, *secrets):
+    """Redact secret values from captured output before passthrough."""
+    for s in secrets:
+        if s and len(s) >= 4:
+            text = text.replace(s, "[redacted]")
+    return text
+
+
+def _mask_email(identifier):
+    local, _, domain = identifier.partition("@")
+    return (local[:1] + "***@" + domain) if domain else "***"
+
+
 def _load_registry():
     path = "/home/super/Projects/NetVM/bin/netvm-registry.py"
     spec = importlib.util.spec_from_file_location("netvm_registry", path)
@@ -93,11 +106,21 @@ def main():
             print("ERROR: no code on stdin", file=sys.stderr)
             return 1
         cmd += ["--otp", code]
-    r = subprocess.run(cmd, capture_output=True, text=True, timeout=220)
+    try:
+        r = subprocess.run(cmd, capture_output=True, text=True,
+                           timeout=220)
+    except subprocess.TimeoutExpired:
+        # NB: TimeoutExpired str() includes the argv (with secrets) -
+        # never let it reach stderr uncaught.
+        print("ERROR: signin step timed out", file=sys.stderr)
+        return 1
     # Propagate the signin script's contract:
-    # 0 = done, 2 = OTP prompt reached, 3 = NEEDS_HUMAN, 4 = NEEDS_SIGNUP
-    sys.stdout.write(r.stdout)
-    sys.stderr.write(r.stderr)
+    # 0 = done, 2 = OTP prompt reached, 3 = NEEDS_HUMAN, 4 = NEEDS_SIGNUP.
+    # Scrub: the signin script echoes the identifier/code in progress
+    # output; redact before passthrough (server scrubs too, defense
+    # in depth).
+    sys.stdout.write(_scrub(r.stdout, identifier, code))
+    sys.stderr.write(_scrub(r.stderr, identifier, code))
 
     if r.returncode == 4:
         log_entry = {
@@ -105,7 +128,7 @@ def main():
             "type": "onboarding_needs_signup",
             "node": args.node,
             "service": args.service,
-            "email": identifier,
+            "email_masked": _mask_email(identifier),
             "status": "needs_signup",
             "action_required": "ask_client_to_sign_up",
             "signup_url": "https://muse.ai"