Nodes Viewer Mode: a crash that could happen when the nodes header was interpreted as an UTF-8 value should be fixed for good now (#827)

UDBScript: setting an UDMF string field to an empty string will not remove the field anymore, but actually set it to an empty string

Disabled visual sloping for game configurations that do not support plane equation slopes. Fixes #828
Added toasts for visual sloping events

Improved UDBScript to version 5:

- Added Plane class
- Added BlockMap, BlockEntry, and BlackMapQueryResult classes
- Sector class
  - Added getLabelPositions method to get the position of sector labels (where tags, effects etc. are displayed)
- Added support for JavaScript BigInt for UDMF fields. This means it's not necessary anymore to use UniValue to assign integers to new UDMF fields. Instead it can be done like this: sector.fields.my_int_field = 1n;
- Added type information file (udbscript.d.ts)

Behavior can be configured in the "Toasts" tab in the preferences.

3D Floor Mode: added support for UDMF game configurations without support for sectors with multiple tags (i.e. Zandronum)

Tag Range plugin: fixed a problem where the new tags were not displayed in Sectors Mode when selection numbering was disabled. Fixes #795

Sectors Mode: fixed a regression where sector labels were not updated after editing sectors. Fixes #793

Fixed a regression where editing map elements did not preserve the selection order, but used the index order instead. Fixes #791

- editing a highlighted, not selected map element will deselect other selected map elements, then start editing the highlighted map element
- dragging a highlighted, not selected map element will deselect other selected map elements, then start dragging the highlighted map element
- dragging a single map element will keep its selection state. I.e. dragging a selected map element will not deselect it after dragging anymore
  - dragging a highlighted, not selected thing will not select it after dragging
- dragging a highlighted, not selected sector, while other sectors are selected, will only drag the highlighted sector, and not the selected sector (and deselect the selected sectors)

Linedefs Mode: fixed a problem where the "Select Single-sided only" and "Select Double-sided only" actions would still display the selection numbers of deselected linedefs

- Sector Color Picker: fixed a problem where the dialog could not be closed using the "enter" or "ESC" buttons
- Light/Sector Color Picker: fixed a problem where closing the dialog would result in a flicker
- Light Color Picker: fixed a problem where canceling the dialog would not revert the color settings

Sound Environment Mode: fixed an issue that caused building sound environments to fail when the arguments of the Sound Environment thing had unexpected values.

Sound Environment Mode: fixed a crash that happened when exiting Draw Lines Mode with the "edit" action and returning to Sound Environment Mode. Fixes #755

Things: fixed an issue where inserting a new thing would not immediately apply ZScript user variables

Visplane Explorer Mode: fixed an issue that caused a crash when the map doesn't have nodes the Visplane Explorer Mode understands. Fixes #736

Visual Mode: fixed an issue where using the "apply camera rotation to things" action did not update the thing cages properly

Draw Settings docker: fixed an issue where toggling the texture check boxes stopped texture overrides from being applied

Map element associations: fixed a problem where things that have a argument of type tag set to 0 were referencing all things with tag 0. Fixes #718

Linedefs Mode: fixed a crash that could happen when the mouse was moved out of the map control while an UDBScript was modifying the map

Sectors Mode: fixed a crash that could happen when the mouse was moved out of the map control while an UDBScript was modifying the map

Edit Selection Mode: improved handling of texture transformation (still doesn't work 100% correctly)

Map Analysis Mode: fixed an issue where lines were erroneously reported as overlapping in certain situations. Fixes #713

Nodes Viewer Mode: the mode will not engage anymore if ZNODES are found, do to ZDBSP reordering the vertices when rebuilding the nodes. Addresses #659

Visual Mode: Fixed a problem where using visual sloping a slope handle around itself resulted in invalid slopes

UDBScript: added an option to open the selected folder in the Explorer to the context menu of folder items in the file tree