[WC-3485]: fix(app-events-web): remove unexpected spacing caused by widget styles

[r0b1n]

Summary

• The widget-events class had flex-grow: 1, position: relative, and transition styles that caused the widget div to occupy space in flex layouts at runtime
• Since App Events is a purely logical widget with no visual content, it should be hidden (display: none)
• Removed the leftover styles and replaced with display: none

Test plan

• Place an App Events widget inside a flex container in Studio Pro and verify no unexpected spacing appears
• Verify the widget still fires events correctly (no visual regression expected — widget renders nothing)

[github-actions]

AI Code Review

✅ Approved — no issues found

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What was reviewed

File	Change
packages/pluggableWidgets/events-web/src/ui/Events.scss	Removed leftover flex/positioning/transition styles; replaced with display: none
packages/pluggableWidgets/events-web/CHANGELOG.md	Added [Unreleased] / Fixed entry describing the layout fix

Skipped (out of scope): dist/, pnpm-lock.yaml

All CI checks were not retrievable (permission restricted), but the change is purely a CSS/CHANGELOG edit with no logic or test impact.

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Positives

• Correct diagnosis: display: none is the right approach for a purely logical, zero-visual widget — it removes it from all layout algorithms (flex, grid, block flow) rather than just hiding it visually.
• The removed SCSS variables ($brand-primary, $gray-dark) were unused in the file — good cleanup without side effects.
• CHANGELOG entry is user-facing and follows the repo's "widget behavior, not implementation details" convention, placed correctly under [Unreleased] / Fixed.
• PR title follows the [WC-XXXX]: type(scope): description convention and the test plan covers both the visual (no spacing) and functional (events still fire) cases.