Dashboards: Fix missing Ctrl+O keyboard shortcut for crosshair toggle (#111310)

* Dashboard Scenes: Fix missing Ctrl+O keyboard shortcut for crosshair toggle

- Add missing mod+o keybind to dashboard scenes keyboard shortcuts
- Implement crosshair state cycling (Default -> Crosshair -> Tooltip -> Default)
- Add comprehensive unit tests for keyboard shortcuts functionality
- Add e2e test to verify shortcut works and prevents browser file dialog
- Fix ensures parity between legacy and scenes dashboard implementations

Fixes issue where Ctrl+O/Cmd+O was opening browser file dialog instead of
toggling shared crosshair modes in scenes-based dashboards.

* Remove waitForTimeout from e2e test

- Replace arbitrary timeouts with proper element waiting
- Use waitFor with visible state instead of setTimeout
- Improve test reliability and follow Playwright best practices

* Optimize e2e test for crosshair keyboard shortcut

- Remove unnecessary console logging and timeout settings
- Simplify assertions to only check the currently selected radio button
- Improve test performance by reducing DOM queries
- Focus on essential functionality verification

* Fix linting

go.work.sum

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