BREAKING CHANGE: add option to hide exchange features for restricted regions

[kwsantiago]

Summary

• Adds setting to hide exchange UI elements (buy, sell, pay, exchange)
• Useful for users in regions where exchange features are unavailable
• Reduces screen clutter when exchange functionality is not accessible

Changes

• New hideExchangeFeatures setting in settings entity/repository/datasource
• Toggle switch in app settings screen
• Conditionally hide exchange action cards and menu items based on setting
• Database migration to add setting column with default false

Closes #1340

[ethicnology]

This PR once merged will require a new schema version, migrations and migrations tests, applying BREAKING CHANGES flag to warn maintainers during integration

[i5hi]

Nice work on following the architecture.

Once UI decision we have to make is what to do with Swaps/Transfers - its the only button on the centred action button list that isnt related to the exchange and looks awkward on its own.

We will have a discussion about this internally and update.

[basantagoswami]

maybe we can follow this pattern for the swap button on wallet homescreen. taken from the layerz wallet. maybe put the swap button on the left, which would make it easier for people to click on both send and receive using their right thumb

[basantagoswami]

I know the PR is outdated now and needs to be rebased, but a few feedback after running the branch in local (haven't checked the code):

• When you hide the bottom nav bar, the The "Receive" and "Send" buttons end up flush against the bottom edge with no
  padding/margin
• The transfer button needs to be moved elsewhere, maybe to the left of the buttons on the bottom, like I mentioned earlier
• After the button is moved, make sure there is no card/layout sticking up into the pattern above

[kwsantiago]

Comments should be addressed in 0d96a5b