* Used Shared resource for File Handling
* Making use of shared attachment serve functionality
* Added license
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Co-authored-by: Mattermost Build <build@mattermost.com>
* Refactor error usage from the store level up and add API helpers
* Complete API tests
* Fix merge errorResponse calls
* Remove ensure helpers to allow for custom messages on permission errors
* Fix bad import and call
* Remove bad user check on auth that was added as part of the main merge
* Fix empty list test
* Replace deprecated proxy calls to ioutil.ReadAll with io.ReadAll
* Add information to the NotFound errors
* Add context to all remaining errors and address review comments
* Fix linter
* Adapt the new card API endpoints to the error refactor
* Remove almost all customErrorResponse calls
* Add request entity too large to errorResponse and remove customErrorResponse
* Fix linter