[The Task](https://www.pivotaltracker.com/story/show/180887253)
A new (+) button on the left-bottom corner appeared. It may be clicked to open searcher in the middle of the scene, as an alternative to tab key.
https://user-images.githubusercontent.com/3919101/154514279-7972ed6a-0203-47cb-9a09-82dba948cf2f.mp4
# Important Notes
* The window_control_buttons::common was extracted to separate crate `ensogl-component-button` almost without change.
* This includes a severe refactoring of adding nodes in general in the Graph Editor. The whole responsibility of adding new nodes (and starting their editing) was moved to Graph Editor - the Project View only reacts for GE events to show searcher properly.
* The status bar was moved from the bottom-left corner to the middle-top of the scene. It does not collide with (+) button, and plays "notification" role anyway.
* The `interface` debug scene was buggy. The problem was with one expression's span-tree. When I replaced it, the scene works.
* I've removed "new searcher" API, as it is completely outdated.
* I've changed code owners of integration tests to GUI team, as it is the team writing mostly the integration tests (int rust)
[Task link](#181181203).
This is a reincarnation of PR [3273](https://github.com/enso-org/enso/pull/3273).
The maximum zoom factor of Graph Editor is limited to 1.0x. It is not possible to zoom in from the default camera position.
Debug Mode (activated with `ctrl-shift-d` shortcut) allows to zoom up to 100.0x (the previous behavior of Graph Editor).
If you enable Debug Mode, then zoom in and disable Debug Mode - you won't see the immediate change of zoom factor back to 1.0x. But it will "jump" (with animation) back once you make a zoom in/out event with your controls.
Video:
https://user-images.githubusercontent.com/6566674/154037310-1d166737-353e-4ae6-aca1-f7840571ab16.mp4
# Important Notes
This is a reincarnation of PR [3273](https://github.com/enso-org/enso/pull/3273). There are two changes since that PR:
1. Fixed bug with GeoMap zooming described [here](https://github.com/enso-org/enso/pull/3290). This is done by restricting `ZoomEvent` API so that it will never contain `amount` which is equal to `0.0`.
2. A few refactoring changes from https://github.com/enso-org/enso/pull/3289 to simplify code a bit.
- Add parser & handler in IDE for `executionContext/visualisationEvaluationFailed` message from Engine (fixes a developer console error "Failed to decode a notification: unknown variant `executionContext/visualisationEvaluationFailed`"). The contents of the error message will now be properly deserialized and printed to Dev Console with appropriate details.
- Fix a bug in an Enso code snippet used internally by the IDE for error visualizations preprocessing. The snippet was using not currently supported double-quote escaping in double-quote delimited strings. This lack of processing is actually a bug in the Engine, and it was reported to the Engine team, but changing the strings to single-quoted makes the snippet also more readable, so it sounds like a win anyway.
- A test is also added to the Engine CI, verifying that the snippet compiles & works correctly, to protect against similar regressions in the future.
Related: #2815
