refactor: merge CoreCursor into Cursor

NODE-2839

Author: emadum

src/change_stream.ts

@@ -1,7 +1,7 @@
 import Denque = require('denque');
 import { EventEmitter } from 'events';
 import { MongoError, AnyError, isResumableError } from './error';
-import { Cursor, CursorOptions, CursorStream } from './cursor/cursor';
+import { Cursor, CursorOptions, CursorStream, CursorStreamOptions } from './cursor/cursor';
 import { AggregateOperation, AggregateOptions } from './operations/aggregate';
 import { loadCollection, loadDb, loadMongoClient } from './dynamic_loaders';
 import {
@@ -18,7 +18,6 @@ import type { Timestamp, Document } from './bson';
 import type { Topology } from './sdam/topology';
 import type { OperationParent } from './operations/command';
 import type { CollationOptions } from './cmap/wire_protocol/write_command';
-import type { CursorStreamOptions } from './cursor/core_cursor';
 const kResumeQueue = Symbol('resumeQueue');
 const kCursorStream = Symbol('cursorStream');
 

src/cursor/aggregation_cursor.ts

@@ -1,6 +1,5 @@
 import { MongoError } from '../error';
-import { Cursor, CursorOptions } from './cursor';
-import { CursorState } from './core_cursor';
+import { Cursor, CursorOptions, CursorState } from './cursor';
 import type { AggregateOperation, AggregateOptions } from '../operations/aggregate';
 import type { Document } from '../bson';
 import type { Sort } from '../operations/find';

src/cursor/command_cursor.ts

@@ -1,7 +1,6 @@
 import { ReadPreference, ReadPreferenceLike } from '../read_preference';
 import { MongoError } from '../error';
-import { Cursor, CursorOptions } from './cursor';
-import { CursorState } from './core_cursor';
+import { Cursor, CursorOptions, CursorState } from './cursor';
 import type { Topology } from '../sdam/topology';
 import type { CommandOperation } from '../operations/command';