Fix account picker infinite loading during Ledger import

[Maskln]

paired with: https://github.com/AmbireTech/ambire-app/pull/7408

Summary

• Add #setPageGeneration to invalidate in-flight setPage() requests and clear accountsLoading on reset()
• Fix invalid page (<= 0) leaving the spinner active
• Apply pageSize from setInitParams earlier so the UI can become ready sooner
• Improve Ledger error normalization for benign SDK states (none, empty interaction)
• Add test for invalid page clearing accountsLoading

[superKalo]

I don't see the context behind this test. setPage({ page: 0 }) isn't reachable anyways - every caller in the UI already guards it (pagination, navigation, etc).

This either makes no sense, or covers a corner case that's not explained?

Meanwhile the change this PR actually exists for - the #setPageGeneration stale-request guard - has no test coverage.

So either swap this test for one that calls two setPage calls (assert the later page wins), or one where reset() interrupts an in-flight setPage and test if accountsLoading still lands on false.

Those would fail before the fix and actually protect the race, which would ultimately validate that the changes in this PR are actually fixing problem(s).