feat: New toolbar layout, cleaner UI, fallback project icon fix

[aaroniker]

• Implemented the new UI, sidebar toggle, session header and some more actions are in the same toolbar as the screen controls if using macos now, for win the toolbar icon is aligned left
• Fixed the project icon fallback, so no more damaged imgs failing to load
• More, small UI improvements
• Fixed some lint errors, warnings

Screenshot

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No duplicate PRs found

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