## Description
Makes App Sidebar Generally Available
- Removes any feature flag control for App Sidebar
- Removes any older functionalities to handle non App Sidebar IDE
versions like:
- App Settings having an open or close state
- Entity Explorer ability to be hidden
- Removes the announcement for App Sidebar
#### PR fixes following issue(s)
Fixes#29232
#### Type of change
- Chore (housekeeping or task changes that don't impact user perception)
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## Summary by CodeRabbit
- **Refactor**
- Streamlined component logic by consolidating functions and removing
unnecessary dependencies.
- Simplified rendering and logic flow in various editor components for
improved user experience.
- **Style**
- Enhanced styling and layout in the app settings pane and editor
sidebar components.
- **Chores**
- Improved code maintainability by cleaning up unused imports,
variables, and functions.
- **Bug Fixes**
- Addressed UI inconsistencies by removing deprecated feature flags and
adjusting component behavior.
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