Adds AgentNetwork.Zone to the management config and passes it to the
agent-network manager, alongside the existing plumbing in the combined
binary. Nothing reads it yet -- the allocator that stamps it onto new rows
comes next -- so this commit is inert on its own.
Embed Dex as a built-in IdP to simplify self-hosting setup.
Adds an embedded OIDC Identity Provider (Dex) with local user management and optional external IdP connectors (Google/GitHub/OIDC/SAML), plus device-auth flow for CLI login. Introduces instance onboarding/setup endpoints (including owner creation), field-level encryption for sensitive user data, a streamlined self-hosting provisioning script, and expanded APIs + test coverage for IdP management.
more at https://github.com/netbirdio/netbird/pull/5008#issuecomment-3718987393
