feat(analysis/normed_space/hahn_banach/separation): generalize to (locally convex) topological vector spaces (#16796)
Co-authored-by: Moritz Doll <moritz.doll@googlemail.com>
Co-authored-by: Moritz Doll <doll@uni-bremen.de>
Co-authored-by: mcdoll <moritz.doll@googlemail.com>