feat(banking): persist bank connections and manage consent lifecycle

[marianialessandro]

Summary

Adds persistence and consent lifecycle management on top of the banking foundation introduced in #536.

• Persist bank connections, provider identity, and pending authorization state, with migrations and compatibility for existing stored data.
• Handle authorization callbacks, interrupted-flow recovery, reconnect, and revocation through provider-neutral banking contracts.
• Integrate credential settings and lifecycle coordination in the application layer, keeping Enable Banking-specific behavior in its adapter.

This is the second PR in the banking integration series for #481. User-facing setup and connection flows will be introduced in the later UI PR.

Commit structure

1. Validate consent redirects and map connection failures.
2. Persist bank connections and recovery state.
3. Integrate the provider-neutral consent lifecycle.