dev-api: add developer portal, OpenAPI spec, and Flatenbadet case study

- New /developers/ page with API docs, SDKs, pricing, use cases
- OpenAPI 3.0 spec for Orders, Missions, Photos, Analytics
- Case study: Glasskiosken i Flatenbadet — complete ROI analysis
- Updated /order/ with recurring missions and frequency dropdown

services/frilans-payout/node_modules/is-path-inside/index.js

@@ -0,0 +1,12 @@
+'use strict';
+const path = require('path');
+
+module.exports = (childPath, parentPath) => {
+	const relation = path.relative(parentPath, childPath);
+	return Boolean(
+		relation &&
+		relation !== '..' &&
+		!relation.startsWith(`..${path.sep}`) &&
+		relation !== path.resolve(childPath)
+	);
+};