Move System::jsonError to BaseModule->jsonError

- This will ensure headers set in BaseModule->run will be carried in jsonError scenarios
- Make BaseApi->checkThrottleLimit an object method to use BaseModule->jsonError
- Deprecate jsonError() method in Core\System

src/Module/Profile/Profile.php

@@ -89,7 +89,7 @@ class Profile extends BaseProfile
 					header('Cache-Control: max-age=23200, stale-while-revalidate=23200');
 					$this->jsonExit($data, 'application/activity+json');
 				} catch (HTTPException\NotFoundException $e) {
-					System::jsonError(404, ['error' => 'Record not found']);
+					$this->jsonError(404, ['error' => 'Record not found']);
 				}
 			}
 
@@ -97,10 +97,10 @@ class Profile extends BaseProfile
 				// Known deleted user
 				$data = ActivityPub\Transmitter::getDeletedUser($this->parameters['nickname']);
 
-				System::jsonError(410, $data);
+				$this->jsonError(410, $data);
 			} else {
 				// Any other case (unknown, blocked, nverified, expired, no profile, no self contact)
-				System::jsonError(404, []);
+				$this->jsonError(404, []);
 			}
 		}
 	}