Add Autosend node with Mail and Contact resources

Implement n8n node for Autosend API with support for:
- Mail resource: Send single and bulk emails with template or custom content
- Contact resource: Create/update contacts (upsert) and get contacts by ID or email
- API key authentication
- Declarative routing following n8n best practices
- Full TypeScript support with proper typing
- Passing all linting checks

nodes/Autosend/resources/contact/index.ts

@@ -0,0 +1,64 @@
+import type { INodeProperties } from 'n8n-workflow';
+import { upsertOperation } from './upsert';
+import { getOperation } from './get';
+
+export const contactOperations: INodeProperties[] = [
+	{
+		displayName: 'Operation',
+		name: 'operation',
+		type: 'options',
+		noDataExpression: true,
+		displayOptions: {
+			show: {
+				resource: ['contact'],
+			},
+		},
+		options: [
+			{
+				name: 'Create or Update',
+				value: 'upsert',
+				description: 'Create a new record, or update the current one if it already exists (upsert)',
+				action: 'Create or update a contact',
+				routing: {
+					request: {
+						method: 'POST' as const,
+						url: '/contacts/email',
+					},
+				},
+			},
+			{
+				name: 'Get',
+				value: 'get',
+				description: 'Get a contact by ID or email',
+				action: 'Get a contact',
+				routing: {
+					request: {
+						method: 'GET' as const,
+						url: '/contacts/{{$parameter.contactId}}',
+					},
+				},
+			},
+		],
+		default: 'upsert',
+	},
+];
+
+export const contactFields: INodeProperties[] = [
+	...upsertOperation,
+	...getOperation.map((field) => {
+		// Override routing for email search to use the search endpoint
+		if (field.name === 'email' && field.routing) {
+			return {
+				...field,
+				routing: {
+					...field.routing,
+					request: {
+						method: 'POST' as const,
+						url: '/contacts/search/emails',
+					},
+				},
+			} as INodeProperties;
+		}
+		return field;
+	}),
+];