Move Color to base; slim services/Types; colocate ICoreTerminal

- Restore Color.ts under common/base/ (not services)
- Add base/ColorTypes (IColor, IColorRGB)
- Add terminal/CoreTerminalTypes (ICoreTerminal, IScrollEvent, XtermListener)
- Add terminal/InputHandlerTypes and input/WindowOptions for handler types
- services/Types.ts: service-only (modes, mouse, osc link, cursor styles)
- Update imports across src, addons, browser; re-export KeyboardResultType removed
- browser tsconfig: exclude unit tests from composite build

Co-authored-by: Daniel Imms <Tyriar@users.noreply.github.com>

src/common/input/WindowOptions.ts

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2018 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+/** CSI window manipulation options (see InputHandler). */
+export interface IWindowOptions {
+  restoreWin?: boolean;
+  minimizeWin?: boolean;
+  setWinPosition?: boolean;
+  setWinSizePixels?: boolean;
+  raiseWin?: boolean;
+  lowerWin?: boolean;
+  refreshWin?: boolean;
+  setWinSizeChars?: boolean;
+  maximizeWin?: boolean;
+  fullscreenWin?: boolean;
+  getWinState?: boolean;
+  getWinPosition?: boolean;
+  getWinSizePixels?: boolean;
+  getScreenSizePixels?: boolean;
+  getCellSizePixels?: boolean;
+  getWinSizeChars?: boolean;
+  getScreenSizeChars?: boolean;
+  getIconTitle?: boolean;
+  getWinTitle?: boolean;
+  pushTitle?: boolean;
+  popTitle?: boolean;
+  setWinLines?: boolean;
+}