feat: implement address management components and functionality

[Abhishek-Punhani]

Implemented address management components and functionality

Description

• Add AddressPicker component for selecting and managing saved addresses.
• Enhance PreferencesPage to include address management features.
• Added Use Saved Address in cart view to use saved address during checkout.
• Add unit tests for saved address helper functions.
• Update local storage helper functions to manage saved addresses.
• Define SavedAddress type in typescript types.

Resolved or fixed issue

Fixes #374

Screenshots (if applicable)

2026-04-10.23-17-11.mp4

Affirmation

• My code follows the CONTRIBUTING.md guidelines

[vercel]

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[arnavkirti]

Thanks for the solid work on this PR - Would like to point out some things:

• Please confirm that we validate all required fields (name, address, city, state, zip, country) both on the client and at the boundary where these are sent to the backend.
• Consider what happens if zip or country are missing or malformed (especially for non‑US addresses) and add tests to cover these edge cases.
• isDefault is a boolean on SavedAddress, but there is no obvious guard to ensure only one address can be default at a time.
• Can you add logic (and tests) to ensure we never end up with multiple defaults, and clarify the behavior when the current default is deleted?
• Please double‑check that all interactive elements in the Address picker / management UI are keyboard accessible and have appropriate ARIA labels where needed.
• If we are showing destructive actions (like delete), a confirmation step or undo pattern would be helpful to prevent accidental loss of an address.
• it would be good to have a few focused tests on:
  • Rendering of saved addresses list.
  • Creating a new address and setting it as default.
  • Editing/deleting an existing address.
  • Ensuring only one default address after updates.