#19805 webviews: fix chat-header-changes test after tooltip shortcut hints

Fixes the base red in webviews/test/chat-header-changes.test.tsx from #19770.

#19770 moved the header buttons' shortcut out of the title into data-tooltip-shortcut, which the themed tooltip draws as a hint in the secondary ink. The button's title and accessible name are now the plain "Changes". The test still expected "Changes (⌃⇧⌘G)" in the title. It now expects the plain title and the shortcut in data-tooltip-shortcut.

Testing

• bun test test/chat-header-changes.test.tsx: red on base (title "Changes" vs expected "Changes (⌃⇧⌘G)"), 1 pass after this change.
• test/chat-header-tooltips.test.tsx and test/chat-menu-copy.test.tsx, the other tests that assert shortcut text: both pass.

Changelog

none

🤖 Generated with Claude Code

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Summary by cubic

Updates the chat header "Changes" test so it passes after #19770 moved header button shortcuts out of title into data-tooltip-shortcut.

• The test now expects the plain "Changes" title and verifies the shortcut lives in data-tooltip-shortcut instead.