TE: Timeline control improvements

[Lwmte]

• There's a "ghost" timeline zoom-out animation on editor start-up. It looks strange because zoom-out animation is not motivated by any user input. Timeline should not perform this animation at the startup.
• There's no divider between timeline control region and level statistics / step height region, which may confuse builders and visually merge those regions for them. It is recommended to add a splitter between two regions (preferably within flyby timeline control panel, as it may be hidden, and always exists on top of statistics panel).
• If you have some non-flyby object selected, and then select a camera in the timeline, gizmo will stay on previous object (see attached video).
  https://github.com/user-attachments/assets/09de2114-cbc0-46ef-8f6e-de791c5a08a7
• If you continuously increase FOV in edit flyby camera dialog and push it above 180, editor will crash with Matrix4x4 exception. FOV must be limited to < 180.