feat: custom icon for transactions

[Syn-McJ]

Issue being fixed or feature implemented

We want to associate an icon with a transaction and potentially synchronize it as transaction metadata with the platform.

What was done?

• Cherry-pick the tx metadata refactoring from the private note PR.
• Table for custom icons in the DB.
• Save the icon data into the DB if not present, and associate its ID with the transaction.
• Load the icon in the Gift Card details screen.

How Has This Been Tested?

QA

Breaking Changes

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have made corresponding changes to the documentation

For repository code-owners and collaborators only

• I have assigned this pull request to a milestone

[pankcuf]

LGTM