Create AccessibleView, use it for terminal and chat accessibility help menus

[meganrogge]

Fixes #183363
fixes #179689

Remaining help menu adoption (more complex so in separate PRs):

• notebook Add notebook accessibility help menu #184176
• editor make accessibility help menu more accessible #179689
• diff editor - after that refactor has happened

To do later:

• adopt in hovers Terminal accessibility help not being read automatically by orca #173911 (comment)
• chat responses https://github.com/microsoft/vscode-copilot/issues/284
• notebook output cells Accessibility feature in output cell of notebook with VsCode #183208
• improve inline chat menu https://github.com/microsoft/vscode-copilot/issues/313
• add a way to view next/previous content in AccessibleView #184612
• consider using this as the basis for terminal accessible buffers
• add border around accessible view #184618

demo.mov

[rebornix]

I wonder if it makes sense to leverage MultiCommand

vscode/src/vs/editor/browser/editorExtensions.ts

Lines 193 to 194 in d4f29ca

	export class MultiCommand extends Command {

so it's a single command for Show Accessibility Help View in all places, which can give us benefits of:

• Single command contribution, each contributor only needs to register a provider other than both the provider and the action contribution
• If users want to change the keybinding, they don't have to change the keybindings for every *.showAccessibilityHelpView command.
• This command can then also be added to the Menu

Current approach doesn't seem to scale.

[meganrogge]

Yes @rebornix i thought the same and was unaware such a thing existed. Thanks!

[meganrogge]

@rebornix i'll need to defer that to the PR where I convert the editor accessibility help action to use this - currently, what's happening is that is overriding the terminal's action since there's no precondition. I'll need to add a when clause to the addImplementation arguments.

Edit:

got it to work

addressed

addressed