feat: port Analysis.InnerProductSpace.TwoDim (#4602)

Co-authored-by: Jeremy Tan Jie Rui <reddeloostw@gmail.com>
Co-authored-by: Parcly Taxel <reddeloostw@gmail.com>

Author: urkud

Mathlib.lean

@@ -586,6 +586,7 @@ import Mathlib.Analysis.InnerProductSpace.PiL2
 import Mathlib.Analysis.InnerProductSpace.Positive
 import Mathlib.Analysis.InnerProductSpace.Projection
 import Mathlib.Analysis.InnerProductSpace.Symmetric
+import Mathlib.Analysis.InnerProductSpace.TwoDim
 import Mathlib.Analysis.InnerProductSpace.l2Space
 import Mathlib.Analysis.LocallyConvex.AbsConvex
 import Mathlib.Analysis.LocallyConvex.BalancedCoreHull