Draft: feat: add organization_id to SSH keys

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Relates to issue #577243

This MR was created by Duo in Session 1180514

Changes

• Update Key model to automatically populate organization_id field
• Add model validation to ensure organization_id is present for new records
• Update Keys::CreateService to set organization_id from user's organization
• Add callback to derive organization_id from user if not explicitly provided
• Handle edge cases where user might not have an organization
• Add comprehensive tests for organization_id handling