Fix duplicate class and annotation placement lint errors

Classes contributed to by more than one file now carry the `partial`
attribute. trains.lua declared its command as `ExpCommand_Artillery`,
which was a copy paste.

`Color.0` and `MapPosition.0` became `.struct` in fmtk 2.1.6.

emmylua rejects `@type` on a function statement or a `do` block, so
those are moved onto the local or replaced by `@param` and `@return`.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

exp_scenario/module/commands/trains.lua

@@ -10,7 +10,7 @@ local format_number = require("util").format_number
 local commands = {}
 
 --- Set all trains to automatic
---- @class ExpCommand_Artillery.commands.artillery: ExpCommand
+--- @class ExpCommand_Trains.commands.set_trains_to_automatic: ExpCommand
 --- @overload fun(player: LuaPlayer, surface: LuaSurface?, force: LuaForce?)
 commands.set_trains_to_automatic = Commands.new("set-trains-to-automatic", { "exp-commands_trains.description" })
     :optional("surface", { "exp-commands_trains.arg-surface" }, Commands.types.surface)