Also attempted to fix material changing and updating the rendered block

Save game details were changed, they may not work properly
Game mode change event no longer sends game data, needs fixing

- Added support for seat enter and exit events and a test for them
- Added support for entering and exiting seat from code
- Changed the Id property of ECS objects to non-abstract, requiring it in the constructor, so that the Player class can inherit EcsObjectBase
- Added a weird constructor to EcsObjectBase that allows running code to determine the object Id
- Added interface for engines that receive entity functions
- Exposed the entity submission scheduler and removed it from FullGameFields because it moved from there
- Made the Game.Enter event only fire after the first entity submission so the game is fully initialized and the local player exists
- Added all seat groups to the dictionary

- Added a wrapper class that handles the individual wrapping of event handlers to individually handle exceptions - now it tracks the wrapped event handlers so it can unregister them properly
- Fixed an exception that happened when two ECS objects were created with the same EGID
- Added support for returning an existing ECS object if it exists instead of always creating a new one
- Added a parameter to the entity query extension methods to override the group of the ECS object (could be used for the player properties)

Removed old dependencies, including uREPL
Added new block IDs
Implemented basic command handling to support existing mod commands

Also added two port name properties directly to the wires
Also added support for converting OptionalRefs to Nullables

Added check for time mode toggle to avoid crashing the game
Added support for having the ref folder outside the solution in gen_csproj.py
Removed BlockIdentifiers class
Added check for invalid player ID when placing blocks
Resolved compilation errors

Probably

Using QueryEntityOptional directly with the player properties
Character structs are camera structs in build mode
The FlyCam rotation is not updated in build mode, only the camera is

Fixed prefab update for nonexistent blocks
Removed Type from block placed/removed event args
Added test to check the block ID enum (whether it has any extra or missing IDs)
Added test to place every block on the ID enum
Added test to set and verify each property of each block type (type-specific properties are also set when they can be through the API)
Added support for enumerator test methods with exception handling

Added property to get the camera from the player
Removed pointer magic

Added support for getting the player's current building mode (build, color, config, blueprint)
Added support for getting the current game's mode (building, playing, prefab etc.)

Fixed getting the selected blueprint
Fixed block groups not being assigned to first block

Added a way to store block groups as blueprints
Blocks can be added/removed from block groups, although it doesn't work well atm
Added some patches to the test class in an attempt to debug an unrelated issue
Added a command to test placing a block group
Added a SelectedBlueprint property to the Player class

Removed BlockIdentifiers.OWNED_BLOCKS as the original got replaced with an array
Added the correct group for each supported functional block
Removed EntityFactory property from IEntitySerializer as it is provided on deserialization

Fixed setting player properties
Changed player rotation to float3
Added constructor for BlockColor with an index param
Improved Player.Exists() ~~hopefully~~

A bit hacky, but it works

Placement, movement, rotation, removal
Block looked at (in Player class), connected blocks