fix(macos): make channel/user/chat/activity views reachable by VoiceOver

Setting accessibilityLabel on the NSScrollView wrappers turned them into
leaf elements, so VoiceOver never descended into the document views
(NSOutlineView/NSTableView/NSTextView) inside. Tab still worked because
the key-view loop is independent of the accessibility tree.

Also removed the redundant setAccessibilityRole calls on the document
views — they already default to those roles, and re-setting the same
role can interfere with the view's custom a11y implementation.

Matches the pattern already used in ConnectWindowController, whose
server table VoiceOver reaches correctly.

clients/apple/macOS/VoiceCatMac/Windows/MainWindowController.swift

@@ -190,13 +190,11 @@ final class MainWindowController: NSWindowController, NSWindowDelegate {
         channelOutlineView.doubleAction = #selector(channelDoubleClicked)
         channelOutlineView.target = self
         channelOutlineView.setAccessibilityLabel("Channel list")
-        channelOutlineView.setAccessibilityRole(.outline)
 
         let sv = NSScrollView()
         sv.documentView = channelOutlineView
         sv.hasVerticalScroller = true
         sv.borderType = .noBorder
-        sv.setAccessibilityLabel("Channel list")
 
         let menu = NSMenu()
         menu.delegate = self
@@ -214,7 +212,6 @@ final class MainWindowController: NSWindowController, NSWindowDelegate {
         userTableView.doubleAction = #selector(userDoubleClicked)
         userTableView.target = self
         userTableView.setAccessibilityLabel("Users in current channel")
-        userTableView.setAccessibilityRole(.table)
 
         let menu = NSMenu()
         menu.delegate = self
@@ -224,13 +221,11 @@ final class MainWindowController: NSWindowController, NSWindowDelegate {
         sv.documentView = userTableView
         sv.hasVerticalScroller = true
         sv.borderType = .noBorder
-        sv.setAccessibilityLabel("Users in current channel")
         return sv
     }
 
     private func buildChatPanel() -> NSView {
         chatTextView.setAccessibilityLabel("Chat messages")
-        chatTextView.setAccessibilityRole(.textArea)
         chatTextView.textContainerInset = NSSize(width: 4, height: 4)
         chatTextView.isAutomaticQuoteSubstitutionEnabled = false
 
@@ -238,7 +233,6 @@ final class MainWindowController: NSWindowController, NSWindowDelegate {
         sv.documentView = chatTextView
         sv.hasVerticalScroller = true
         sv.borderType = .noBorder
-        sv.setAccessibilityLabel("Chat messages")
         return sv
     }
 
@@ -249,13 +243,11 @@ final class MainWindowController: NSWindowController, NSWindowDelegate {
         activityTableView.dataSource = self
         activityTableView.delegate = self
         activityTableView.setAccessibilityLabel("Activity log")
-        activityTableView.setAccessibilityRole(.table)
 
         let sv = NSScrollView()
         sv.documentView = activityTableView
         sv.hasVerticalScroller = true
         sv.borderType = .noBorder
-        sv.setAccessibilityLabel("Activity log")
         return sv
     }