[REF-3321] implement var operation decorator (reflex-dev#3698)

* implement var operation decorator

* use older syntax

* use cast and older syntax

* use something even simpler

* add some tests

* use old union tactics

* that's not how you do things

* implement arithmetic operations while we're at it

* add test

* even more operations

* can't use __bool__

* thanos snap

* forgot ruff

* use default factory

* dang it darglint

* i know i should have done that but

* convert values into literalvars

* make test pass

* use older union tactics

* add test to string var

* pright why do you hate me 🥺

reflex/experimental/vars/__init__.py

@@ -1,18 +1,20 @@
 """Experimental Immutable-Based Var System."""
 
-from .base import ArrayVar as ArrayVar
-from .base import BooleanVar as BooleanVar
-from .base import ConcatVarOperation as ConcatVarOperation
-from .base import FunctionStringVar as FunctionStringVar
-from .base import FunctionVar as FunctionVar
 from .base import ImmutableVar as ImmutableVar
-from .base import LiteralArrayVar as LiteralArrayVar
-from .base import LiteralBooleanVar as LiteralBooleanVar
-from .base import LiteralNumberVar as LiteralNumberVar
 from .base import LiteralObjectVar as LiteralObjectVar
-from .base import LiteralStringVar as LiteralStringVar
 from .base import LiteralVar as LiteralVar
-from .base import NumberVar as NumberVar
 from .base import ObjectVar as ObjectVar
-from .base import StringVar as StringVar
-from .base import VarOperationCall as VarOperationCall
+from .base import var_operation as var_operation
+from .function import FunctionStringVar as FunctionStringVar
+from .function import FunctionVar as FunctionVar
+from .function import VarOperationCall as VarOperationCall
+from .number import BooleanVar as BooleanVar
+from .number import LiteralBooleanVar as LiteralBooleanVar
+from .number import LiteralNumberVar as LiteralNumberVar
+from .number import NumberVar as NumberVar
+from .sequence import ArrayJoinOperation as ArrayJoinOperation
+from .sequence import ArrayVar as ArrayVar
+from .sequence import ConcatVarOperation as ConcatVarOperation
+from .sequence import LiteralArrayVar as LiteralArrayVar
+from .sequence import LiteralStringVar as LiteralStringVar
+from .sequence import StringVar as StringVar