feat(cryptography): add create signature action

packages/backend/src/apps/cryptography/actions/create-rsa-sha256-signature/index.js

@@ -0,0 +1,51 @@
+import crypto from 'node:crypto';
+import defineAction from '../../../../helpers/define-action.js';
+
+export default defineAction({
+  name: 'Create Signature',
+  key: 'createSignature',
+  description: 'Create a digital signature using the specified algorithm, secret key, and message.',
+  arguments: [
+    {
+      label: 'Algorithm',
+      key: 'algorithm',
+      type: 'dropdown',
+      required: true,
+      value: 'RSA-SHA256',
+      description: 'Specifies the cryptographic hash function to use for HMAC generation.',
+      options: [
+        { label: 'RSA-SHA256', value: 'RSA-SHA256' },
+      ],
+      variables: true,
+    },
+    {
+      label: 'Message',
+      key: 'message',
+      type: 'string',
+      required: true,
+      description: 'The input message to be signed.',
+      variables: true,
+    },
+    {
+      label: 'Private key',
+      key: 'privateKey',
+      type: 'string',
+      required: true,
+      description: 'The RSA private key in PEM format used for signing.',
+      variables: true,
+    }
+  ],
+
+  async run($) {
+    const signer = crypto.createSign($.step.parameters.algorithm);
+    signer.update($.step.parameters.message);
+    signer.end();
+    const signature = signer.sign($.step.parameters.privateKey, 'hex');
+
+    $.setActionItem({
+      raw: {
+        signature
+      },
+    });
+  },
+});