✏ README, fix start-once bug and refactor

- Added some configuration and running to README
- Refactored some code
- Fixed exception when stopping a start-once script
- Only allow running with pnpm
- Moved transactions into sparebank1Api.ts
- Formatted

README.md

@@ -1,3 +1,28 @@
 # Sparebank1 ActualBudget Integration
 
 🔧 WIP!
+
+### Setting up the environment
+
+In order to start the application, a `.env.local` file must be present at the root level. The possible and required
+fields
+can be found in the [.env.example](.env.example) file and `config.ts`.
+
+For running integration tests, the `.env.test.local` file must be present at the root level, with Actual fields present.
+
+HTTP requests can be used from an IDE via the .http files. Secrets must be placed in a file called
+`http-client.private.env.json` in the [httpRequests](httpRequests) directory. See the .http files for required values.
+
+### Running the application
+
+Start the application using a CronJob that runs at a given time. Can be stopped using an interrupt (^C)
+
+```shell
+pnpm start
+```
+
+Start the application without a CronJob, it will run once, then shutdown.
+
+```shell
+pnpm start-once
+```