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/eslint/messages/plugin-missing.js

@@ -0,0 +1,19 @@
+"use strict";
+
+module.exports = function(it) {
+    const { pluginName, resolvePluginsRelativeTo, importerName } = it;
+
+    return `
+ESLint couldn't find the plugin "${pluginName}".
+
+(The package "${pluginName}" was not found when loaded as a Node module from the directory "${resolvePluginsRelativeTo}".)
+
+It's likely that the plugin isn't installed correctly. Try reinstalling by running the following:
+
+    npm install ${pluginName}@latest --save-dev
+
+The plugin "${pluginName}" was referenced from the config file in "${importerName}".
+
+If you still can't figure out the problem, please stop by https://eslint.org/chat/help to chat with the team.
+`.trimStart();
+};