Add support for Windows Terminal (#10784)

* Bring over ConsoleUIATextInfo refactoring from #10716.

* Add WinTerminalUIA

* Style.

* Review actions.

* microsoft/terminal#4495: support fixed GetVisibleRanges.

* KeyboardHandlerBasedTypedCharSupport -> EnhancedTermTypedCharSupport, add _shouldUseToUnicodeEx flag and set False for WinTerminalUIA.

* Update doc comments.

* Update copyrights.

* Review actions.

* Factor out bounding into separate method.

* Re-introduce KeyboardHandlerBasedTypedCharSupport.

* Fix UIA console support for newer Windows Console builds.

* Revert copyright header changes.

* Revert another no longer necessary copyright header change.

* Fix comments.

* Update docstring.

* Review actions.

* Update source/NVDAObjects/behaviors.py

Co-Authored-By: Leonard de Ruijter <leonardder@users.noreply.github.com>

* Add class docstring.

* Optimization: clear character buffers when reporting new lines.

This saves us from scanning the old and new lines twice in _calculateNewText (once for diffing and once for finding nonblank indices), and fixes typed word reporting for 21H1 console.

This new approach does not resolve #10942.

* Update inaccurate information in user guide.

Co-authored-by: Leonard de Ruijter <leonardder@users.noreply.github.com>

source/NVDAObjects/UIA/__init__.py

@@ -1,8 +1,9 @@
-#NVDAObjects/UIA/__init__.py
-#A part of NonVisual Desktop Access (NVDA)
-#This file is covered by the GNU General Public License.
-#See the file COPYING for more details.
-#Copyright (C) 2009-2019 NV Access Limited, Joseph Lee, Mohammad Suliman, Babbage B.V., Leonard de Ruijter
+# NVDAObjects/UIA/__init__.py
+# A part of NonVisual Desktop Access (NVDA)
+# This file is covered by the GNU General Public License.
+# See the file COPYING for more details.
+# Copyright (C) 2009-2020 NV Access Limited, Joseph Lee, Mohammad Suliman,
+# Babbage B.V., Leonard de Ruijter, Bill Dengler
 
 """Support for UI Automation (UIA) controls."""
 
@@ -948,6 +949,10 @@ def findOverlayClasses(self,clsList):
 		):
 			from . import winConsoleUIA
 			winConsoleUIA.findExtraOverlayClasses(self, clsList)
+		elif UIAClassName == "TermControl":
+			from . import winConsoleUIA
+			clsList.append(winConsoleUIA.WinTerminalUIA)
+
 		# Add editableText support if UIA supports a text pattern
 		if self.TextInfo==UIATextInfo:
 			if UIAHandler.autoSelectDetectionAvailable: