[MIRROR] Removes stupid listlike var access code (#28658)

* Removes stupid listlike var access code (#84648)

## About The Pull Request

[Removes all other listlike var
accesses](https://github.com/tgstation/tgstation/pull/84648/commits/4c5996b5c8b1da63740e8b4bf998b6cb6eadac33)

Also fucking dumpsters an unused proc that allowed for arbitrary
variable modifcation. Bad juju

This is undefined behavior and errors in later 515 versions. also it's
stupid as hell

* Removes stupid listlike var access code

---------

Co-authored-by: LemonInTheDark <58055496+LemonInTheDark@users.noreply.github.com>

code/controllers/subsystem/research.dm

@@ -7,7 +7,7 @@ SUBSYSTEM_DEF(research)
 	//TECHWEB STATIC
 	var/list/techweb_nodes = list() //associative id = node datum
 	var/list/techweb_designs = list() //associative id = node datum
-	var/list/datum/design/item_to_design = list() //typepath = list of design datums
+	var/list/list/datum/design/item_to_design = list() //typepath = list of design datums
 
 	///List of all techwebs, generating points or not.
 	///Autolathes, Mechfabs, and others all have shared techwebs, for example.

code/controllers/subsystem/spatial_gridmap.dm

@@ -234,7 +234,7 @@ SUBSYSTEM_DEF(spatial_grid)
 	. = list()
 
 	//technically THIS list only contains lists, but inside those lists are grid cell datums and we can go without a SINGLE var init if we do this
-	var/list/datum/spatial_grid_cell/grid_level = grids_by_z_level[center_turf.z]
+	var/list/list/datum/spatial_grid_cell/grid_level = grids_by_z_level[center_turf.z]
 
 	switch(type)
 		if(SPATIAL_GRID_CONTENTS_TYPE_CLIENTS)