L10, L11: Fix robot not being moved by move_local_x (#1229)

Previously, when running move_local_x, the robot didn't seem to move.
This happened because the node that was actually receiving the message
move_local_x was the scene root, which was the parent of both Robot and
Camera0D. This means that the Robot was actually moving but the
Camera2D was moving as well.

The fix is basically the same change in both lessons:
- Moved the scene script from the robot to the scene root (in L11 also
removed the Built-in script from the scene root).
- Made the Camera2D top level inside _ready() so its position will be
independent from the scene root, so when the root is moved by
move_local_x, the Robot moves away while the Camera2D stays in place.

Fixes #1228

chore: update gitignore to ignore lgd files

make sure web and staging web builds are different

chore: revert exporting only some resources in the projet

With this option, newly added resources are not included in exports by default so it is error-prone

chore: change mouse filters on end screen

chore: update changelog for release 1.5.2

chore: update changelog and version for release 1.5.1

chore: update changelog and version for release 1.5.0

content: add FR, PT, PT_BR, and TR translations

chore: add missing changelog for preview releases made before 1.4.0