feat(Analysis/Normed/Module): add bornology and T2 instances for WeakSpace

[mike1729]

Register the norm bornology on WeakSpace 𝕜 E and prove that it coincides with the von Neumann bornology of the weak topology.

New declarations

• WeakSpace.instBornology: norm bornology inherited from E.
• WeakSpace.instT2Space: Hausdorff via Hahn–Banach separation.
• WeakSpace.norm_topology_le_weakSpace_topology: the weak topology is coarser than the norm topology.
• WeakSpace.isBounded_iff_isVonNBounded: norm-boundedness equals weak von Neumann boundedness (no [CompleteSpace E] needed).

---

• depends on: refactor(LocallyConvex,Topology): split WeakDual/WeakSpace and rename WeakBilin #37027

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[mathlib-dependent-issues]

This PR/issue depends on:

• refactor(LocallyConvex,Topology): split WeakDual/WeakSpace and rename WeakBilin #37027
  By Dependent Issues (🤖). Happy coding!

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