* fix: Handle missing encryption keys gracefully on providers page
When Active Record encryption keys are not configured, the settings/providers
page would crash with an unhandled exception. This change catches the
ActiveRecord::Encryption::Errors::Configuration error and displays a
friendly error message instead, explaining that encryption credentials
need to be configured before using sync providers.
https://claude.ai/code/session_015nPsLWkr12i5ok5bwLtA7p
* Simplify rescue block
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Co-authored-by: Claude <noreply@anthropic.com>