Fix Cmd+V paste not working in GitHub sign-in WebView

[Copilot]

WKWebView on macOS silently consumes keyboard equivalents (Cmd+V, etc.) instead of forwarding them through the AppKit responder chain to web content. Right-click paste worked because it goes through a separate context menu path.

Changes

• GitHubWebAuthClient.swift: Introduces a private EditableWebView: WKWebView subclass that overrides performKeyEquivalent(with:) to dispatch editing shortcuts via NSApp.sendAction:

private class EditableWebView: WKWebView {
    override func performKeyEquivalent(with event: NSEvent) -> Bool {
        guard event.modifierFlags.contains(.command),
              let key = event.charactersIgnoringModifiers else {
            return super.performKeyEquivalent(with: event)
        }
        switch key {
        case "v": return NSApp.sendAction(#selector(NSText.paste(_:)),      to: nil, from: self)
        case "c": return NSApp.sendAction(#selector(NSText.copy(_:)),       to: nil, from: self)
        case "x": return NSApp.sendAction(#selector(NSText.cut(_:)),        to: nil, from: self)
        case "a": return NSApp.sendAction(#selector(NSText.selectAll(_:)),  to: nil, from: self)
        default:  return super.performKeyEquivalent(with: event)
        }
    }
}

• showLoginWindow() now instantiates EditableWebView instead of plain WKWebView. All other behaviour is unchanged.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Paste does not work on sign in page</issue_title>
<issue_description>For some reason paste does not work on the sign in page using cmd-v however it is available when right clicking in the password box.

Pasting passwords should be allowed.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Paste does not work on sign in page #16

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[lazzurs]

@copilot rebase

[Copilot]

@copilot rebase

Rebasing requires a force push, which isn't available in this environment. Could you rebase the branch manually, or merge the latest main into this branch? The code change itself is a single-file, non-conflicting addition so it should apply cleanly.