Colocate buffer types in buffer/Types.ts

The import/no-cycle refactor had moved IBuffer, IBufferSet, and related
cell/line types into src/common/Types.ts, with buffer/Types.ts only
re-exporting them. That inverted the natural module boundary and made
buffer code depend on the top-level types hub.

Define buffer-owned types in buffer/Types.ts instead:
- CharData, IExtendedAttrs, IAttributeData, ICellData, IBufferLine
- IMarker, IBuffer, IBufferSet, BufferIndex

Restore UnderlineStyle to buffer/Constants.ts (used by IExtendedAttrs)
and remove those definitions from Types.ts.

buffer/Types.ts imports only what it needs from outside the buffer layer:
ICircularList and ICharset from Types, IDisposable from Lifecycle,
IEvent from Event, and UnderlineStyle from Constants. Types.ts does not
import buffer/Types.ts, so the previous Types <-> buffer cycle stays broken.

Update imports across common, browser, headless, addons, and tests to use
common/buffer/Types for buffer types rather than common/Types.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/browser/OscLinkProvider.test.ts

@@ -8,7 +8,8 @@ import { OscLinkProvider } from './OscLinkProvider';
 import { ILink } from './Types';
 import { createCellData, MockBufferService, MockOptionsService } from '../common/TestUtils.test';
 import { IBufferService, IOscLinkService } from '../common/services/Services';
-import { IBufferLine, IOscLinkData } from '../common/Types';
+import { IOscLinkData } from '../common/Types';
+import { IBufferLine } from '../common/buffer/Types';
 
 class TestOscLinkService implements IOscLinkService {
   public serviceBrand: any;

src/browser/OscLinkProvider.ts

@@ -6,7 +6,7 @@
 import { IBufferRange, ILink } from './Types';
 import { ILinkProvider } from './services/Services';
 import { CellData } from '../common/buffer/CellData';
-import { IBufferLine } from '../common/Types';
+import { IBufferLine } from '../common/buffer/Types';
 import { IBufferService, IOptionsService, IOscLinkService } from '../common/services/Services';
 
 export class OscLinkProvider implements ILinkProvider {

src/browser/Terminal.test.ts

@@ -9,7 +9,7 @@ import { assert } from 'chai';
 import { DEFAULT_ATTR_DATA } from '../common/buffer/BufferLine';
 import { CellData } from '../common/buffer/CellData';
 import { MockUnicodeService, createCellData } from '../common/TestUtils.test';
-import { IMarker } from '../common/Types';
+import { IMarker } from '../common/buffer/Types';
 
 const INIT_COLS = 80;
 const INIT_ROWS = 24;

src/browser/TestUtils.test.ts

@@ -7,8 +7,8 @@ import { IDisposable, IMarker, ILinkProvider, IDecorationOptions, IDecoration, I
 import { ICharacterJoinerService, ICharSizeService, ICoreBrowserService, IMouseService, IRenderService, ISelectionService, IThemeService } from './services/Services';
 import { IRenderDimensions, IRenderer, IRequestRedrawEvent } from './renderer/shared/Types';
 import { IColorSet, ITerminal, ILinkifier2, IBrowser, IViewport, ICompositionHelper, CharacterJoinerHandler, IBufferRange, ReadonlyColorSet, IBufferElementProvider } from './Types';
-import { IBuffer, IBufferSet } from '../common/buffer/Types';
-import { IBufferLine, ICellData, IAttributeData, ICircularList, XtermListener, ICharset, ITerminalOptions, ColorIndex } from '../common/Types';
+import { IAttributeData, IBuffer, IBufferLine, IBufferSet, ICellData } from '../common/buffer/Types';
+import { ICircularList, XtermListener, ICharset, ITerminalOptions, ColorIndex } from '../common/Types';
 import { Buffer } from '../common/buffer/Buffer';
 import * as Browser from '../common/Platform';
 import { CoreBrowserTerminal } from './CoreBrowserTerminal';

src/browser/Types.ts

@@ -3,9 +3,9 @@
  * @license MIT
  */
 
-import { CharData, IColor, ITerminalOptions } from '../common/Types';
+import { IColor, ITerminalOptions } from '../common/Types';
+import { CharData, IBuffer } from '../common/buffer/Types';
 import { ICoreTerminal } from '../common/CoreTerminal';
-import { IBuffer } from '../common/buffer/Types';
 import { IDisposable, IRenderDimensions as IRenderDimensionsApi, Terminal as ITerminalApi } from '@xterm/xterm';
 import { channels, css } from '../common/Color';
 import type { IEvent } from '../common/Event';

src/browser/renderer/dom/DomRendererRowFactory.test.ts

@@ -9,7 +9,7 @@ import { DomRendererRowFactory } from './DomRendererRowFactory';
 import { NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR, DEFAULT_ATTR, FgFlags, BgFlags, Attributes, UnderlineStyle } from '../../../common/buffer/Constants';
 import { BufferLine, DEFAULT_ATTR_DATA } from '../../../common/buffer/BufferLine';
 import { BufferLineStringCache } from '../../../common/buffer/BufferLineStringCache';
-import { IBufferLine } from '../../../common/Types';
+import { IBufferLine } from '../../../common/buffer/Types';
 import { CellData } from '../../../common/buffer/CellData';
 import { MockCoreService, MockDecorationService, MockOptionsService, createCellData, NULL_CELL_DATA } from '../../../common/TestUtils.test';
 import { MockCharacterJoinerService, MockCoreBrowserService, MockThemeService } from '../../TestUtils.test';

src/browser/renderer/dom/DomRendererRowFactory.ts

@@ -3,7 +3,8 @@
  * @license MIT
  */
 
-import { IBufferLine, ICellData, IColor } from '../../../common/Types';
+import { IColor } from '../../../common/Types';
+import { IBufferLine, ICellData } from '../../../common/buffer/Types';
 import { INVERTED_DEFAULT_COLOR } from '../shared/Constants';
 import { WHITESPACE_CELL_CHAR, Attributes } from '../../../common/buffer/Constants';
 import { CellData } from '../../../common/buffer/CellData';

src/browser/services/CharacterJoinerService.test.ts

@@ -8,7 +8,7 @@ import { ICharacterJoinerService } from './Services';
 import { CharacterJoinerService } from './CharacterJoinerService';
 import { BufferLine } from '../../common/buffer/BufferLine';
 import { BufferLineStringCache } from '../../common/buffer/BufferLineStringCache';
-import { IBufferLine } from '../../common/Types';
+import { IBufferLine } from '../../common/buffer/Types';
 import { CellData } from '../../common/buffer/CellData';
 import { MockBufferService, createCellData } from '../../common/TestUtils.test';
 

src/browser/services/CharacterJoinerService.ts

@@ -3,7 +3,7 @@
  * @license MIT
  */
 
-import { IBufferLine, ICellData, CharData } from '../../common/Types';
+import { CharData, IBufferLine, ICellData } from '../../common/buffer/Types';
 import { ICharacterJoiner } from '../Types';
 import { AttributeData } from '../../common/buffer/AttributeData';
 import { WHITESPACE_CELL_CHAR, Content } from '../../common/buffer/Constants';

src/browser/services/SelectionService.test.ts

@@ -6,14 +6,13 @@
 import { assert } from 'chai';
 import { SelectionService, SelectionMode } from './SelectionService';
 import { SelectionModel } from '../selection/SelectionModel';
-import { IBufferLine } from '../../common/Types';
+import { IBuffer, IBufferLine } from '../../common/buffer/Types';
 import { MockBufferService, MockOptionsService, MockCoreService, MockMouseStateService, createCellData } from '../../common/TestUtils.test';
 import { BufferLine } from '../../common/buffer/BufferLine';
 import { BufferLineStringCache } from '../../common/buffer/BufferLineStringCache';
 import { IBufferService, IOptionsService } from '../../common/services/Services';
 import { MockCoreBrowserService, MockMouseService, MockRenderService } from '../TestUtils.test';
 import { CellData } from '../../common/buffer/CellData';
-import { IBuffer } from '../../common/buffer/Types';
 import { IRenderService } from './Services';
 
 const TEST_STRING_CACHE = new BufferLineStringCache();

src/browser/services/SelectionService.ts

@@ -11,10 +11,10 @@ import { ISelectionRedrawRequestEvent, ISelectionRequestScrollLinesEvent } from
 import { ICoreBrowserService, IMouseCoordsService, IRenderService, ISelectionService } from './Services';
 import { Disposable, MutableDisposable, toDisposable } from '../../common/Lifecycle';
 import * as Browser from '../../common/Platform';
-import { IBufferLine, ICellData, IDisposable } from '../../common/Types';
+import { IDisposable } from '../../common/Types';
+import { IBuffer, IBufferLine, ICellData } from '../../common/buffer/Types';
 import { getRangeLength } from '../../common/buffer/BufferRange';
 import { CellData } from '../../common/buffer/CellData';
-import { IBuffer } from '../../common/buffer/Types';
 import { IBufferService, ICoreService, IMouseStateService, IOptionsService } from '../../common/services/Services';
 import { Emitter } from '../../common/Event';