fix(cli): set-pin emits PBKDF2 under [security] pin_hash (issue #2)

Was: HMAC-SHA256(random, pin) written to [system] arm_pin_hash —
no verifier in the codebase accepted this output.
Now: PBKDF2-SHA256 via alerts.pin.hash_pin written to [security]
pin_hash, matching what the web and FSM paths verify against.

Also fixes show_cmd to redact the new location.

tests/unit/test_cli_set_pin.py

@@ -0,0 +1,31 @@
+"""Tests for `vigilar config set-pin`."""
+
+from click.testing import CliRunner
+
+from vigilar.alerts.pin import verify_pin
+from vigilar.cli.cmd_config import config_cmd
+
+
+def test_set_pin_outputs_pbkdf2_hash_under_security_section():
+    """The CLI must emit a hash that alerts.pin.verify_pin can validate,
+    and direct the user to [security] pin_hash (not [system] arm_pin_hash)."""
+    runner = CliRunner()
+    result = runner.invoke(config_cmd, ["set-pin"], input="1234\n1234\n")
+
+    assert result.exit_code == 0, result.output
+    # The output must direct the user to the [security] section
+    assert "[security]" in result.output
+    assert "arm_pin_hash" not in result.output
+    assert "pin_hash" in result.output
+
+    # Extract the emitted hash (line starts with `pin_hash = "..."`)
+    hash_line = next(
+        line for line in result.output.splitlines() if line.strip().startswith("pin_hash")
+    )
+    hash_value = hash_line.split('"')[1]
+
+    # Round-trip: the emitted hash must accept the plaintext PIN
+    assert verify_pin("1234", hash_value) is True
+    assert verify_pin("0000", hash_value) is False
+    # And it must be in PBKDF2 format (not the legacy HMAC "secret:mac" format)
+    assert hash_value.startswith("pbkdf2_sha256$")

vigilar/cli/cmd_config.py

@@ -47,8 +47,8 @@ def show_cmd(config_path: str | None) -> None:
         # Redact sensitive fields
         if data.get("web", {}).get("password_hash"):
             data["web"]["password_hash"] = "***"
-        if data.get("system", {}).get("arm_pin_hash"):
-            data["system"]["arm_pin_hash"] = "***"
+        if data.get("security", {}).get("pin_hash"):
+            data["security"]["pin_hash"] = "***"
         if data.get("alerts", {}).get("webhook", {}).get("secret"):
             data["alerts"]["webhook"]["secret"] = "***"
         click.echo(json.dumps(data, indent=2))
@@ -82,14 +82,10 @@ def set_password_cmd(config_path: str | None) -> None:
 
 @config_cmd.command("set-pin")
 def set_pin_cmd() -> None:
-    """Generate an HMAC hash for the arm/disarm PIN."""
-    import hashlib
-    import hmac
-    import os
+    """Generate a PBKDF2 hash for the arm/disarm PIN."""
+    from vigilar.alerts.pin import hash_pin
 
     pin = click.prompt("Enter arm/disarm PIN", hide_input=True, confirmation_prompt=True)
-    secret = os.urandom(32)
-    mac = hmac.new(secret, pin.encode(), hashlib.sha256).hexdigest()
-    hash_str = secret.hex() + ":" + mac
-    click.echo(f"\nAdd this to your vigilar.toml [system] section:")
-    click.echo(f'arm_pin_hash = "{hash_str}"')
+    hash_str = hash_pin(pin)
+    click.echo("\nAdd this to your vigilar.toml [security] section:")
+    click.echo(f'pin_hash = "{hash_str}"')