feat: dbcontext abstraction via dependency

backend/docs/swagger.json

@@ -124,6 +124,17 @@
                     "Auth"
                 ],
                 "summary": "Register an account",
+                "parameters": [
+                    {
+                        "description": "desc",
+                        "name": "request",
+                        "in": "body",
+                        "required": true,
+                        "schema": {
+                            "$ref": "#/definitions/models.RegistrationBeginRequest"
+                        }
+                    }
+                ],
                 "responses": {}
             }
         },
@@ -306,6 +317,21 @@
                     "type": "string"
                 }
             }
+        },
+        "models.RegistrationBeginRequest": {
+            "type": "object",
+            "properties": {
+                "email": {
+                    "type": "string"
+                },
+                "password": {
+                    "description": "TODO: password checking",
+                    "type": "string"
+                },
+                "username": {
+                    "type": "string"
+                }
+            }
         }
     },
     "securityDefinitions": {