WebGLInput.OnEditEnd can cause a crash from Dictionary ThrowKeyNotFoundException

[StefanStrategis]

I think the dictionary key getters need safety checks in every method

For example
if (!instances[id].input.ReadOnly)

I think we need to check if every getter contains
if (!instances.ContainsKey(id)) return;

at jsStackTrace (blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:227976)
at stackTrace (blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:343037)
at blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:8061
at il2cpp::vm::Exception::Raise(Il2CppException*, MethodInfo*) (wasm://wasm/0f007b16:wasm-function[565]:0xa3385)
at il2cpp_codegen_raise_exception(Exception_t*, MethodInfo*) (wasm://wasm/0f007b16:wasm-function[516]:0x9e931)
at ThrowHelper_GetKeyNotFoundException_m6E63D4796191F3AE05973F2CF79BB6DC2D04154F (wasm://wasm/0f007b16:wasm-function[31278]:0x1284939)
at ThrowHelper_ThrowKeyNotFoundException_m6A17735FA486AD43F2488DE39B755AC60BC99CE7 (wasm://wasm/0f007b16:wasm-function[667]:0xa9e22)
at WebGLInput_OnEditEnd_m90E83D4B155D3612972C817C67BF8EA4264CD92A (wasm://wasm/0f007b16:wasm-function[29216]:0x1134db1)
at ReversePInvokeWrapper_WebGLInput_OnEditEnd_m90E83D4B155D3612972C817C67BF8EA4264CD92A (wasm://wasm/0f007b16:wasm-function[75420]:0x2197d1a)
at dynCall_vii (wasm://wasm/0f007b16:wasm-function[48280]:0x1bd0a52)
at dynCallLegacy (blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:15412)
at Object.dynCall (blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:15498)
at input.onchange (blob:https://3dcityplanner.com/9dac1394-c001-46c2-afdd-a7e3d170c32f:9:151097)",