* Added abstractions for PolicyApiService and PolicyService
* Added implementations for PolicyApiService and PolicyService
* Updated all references to new PolicyApiService and PolicyService
* Deleted old PolicyService abstraction and implementation
* Fixed CLI import path for policy.service
* Fixed main.background.ts policyApiService dependency for policyService
* Updated policy-api.service with the correct imports
* [EC-376] Sorted methods order in PolicyApiService
* [EC-376] Removed unused clearCache method from PolicyService
* [EC-376] Added upsert method to PolicyService
* [EC-376] PolicyApiService putPolicy method now upserts data to PolicyService
* [refactor] Introduce a file download service
* [refactor] Point platformUtilsService.saveFile() callers to fileDownloadService.download() instead
* [refactor] Remove platformUtilsService.saveFile()
* [fix] Force send attachments to always download and never open
* [fix] Remove the window property from FileDownloadRequest
* [fix] Move FileDownloadRequest to /abstractions/fileDownload
* [fix] Simplify FileDownloadRequest to a type
* [fix] Move BrowserApi.saveFile logic into BrowserFileDownloadService
* [fix] Use proper blob types for file downloads
* [fix] forceDownload -> downloadMethod on FileDownloadRequest
* [fix] Remove fileType from FileDownloadRequest
* [fix] Make fileType private