make terminal output feature accessible to screen reader users

[meganrogge]

fix #274220

If/when we end up using xterm here instead, we can reuse all of this and just change the getCommandAndOutputAsText function.

[Copilot]

Pull Request Overview

This PR adds an accessible view for chat terminal tool output, allowing screen reader users to access terminal command output from chat tool invocations. It also renames the TerminalChat accessibility verbosity setting to TerminalInlineChat for clarity.

Key changes:

• Adds new ChatTerminalOutputAccessibleView to provide accessible terminal output content
• Introduces inChatTerminalToolOutput context key to track focus state
• Renames AccessibilityVerbositySettingId.TerminalChat to TerminalInlineChat for consistency
• Adds new TerminalChatOutput verbosity setting for the terminal output accessible view
• Implements focus tracking and aria-label management in ChatTerminalToolProgressPart

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/vs/workbench/contrib/terminalContrib/chat/browser/terminalChatAccessibilityHelp.ts	Updates reference from TerminalChat to TerminalInlineChat setting ID
src/vs/workbench/contrib/terminalContrib/chat/browser/terminal.initialHint.contribution.ts	Updates two references from TerminalChat to TerminalInlineChat setting ID
src/vs/workbench/contrib/chat/common/chatContextKeys.ts	Adds new context key for terminal tool output focus tracking
src/vs/workbench/contrib/chat/browser/chatTerminalOutputAccessibleView.ts	New file implementing the accessible view for terminal output
src/vs/workbench/contrib/chat/browser/chatContentParts/toolInvocationParts/chatTerminalToolProgressPart.ts	Adds focus tracking, aria-label management, and accessible view support
src/vs/workbench/contrib/chat/browser/chat.contribution.ts	Registers the new ChatTerminalOutputAccessibleView
src/vs/workbench/contrib/accessibility/browser/accessibilityConfiguration.ts	Renames TerminalChat to TerminalInlineChat and adds new TerminalChatOutput setting
src/vs/platform/accessibility/browser/accessibleView.ts	Adds ChatTerminalOutput provider ID

addressed