Proof of Presence (PoP) – General Availability across all identity providers [GA]

### Value Prop
Proof of Presence requires developers to re-authenticate through their organization's identity provider before completing high-impact actions like merging or approving pull requests. This protection now works across all major SSO providers—including Okta, Ping, and any SAML or OIDC-compatible IdP—so every team benefits regardless of which identity provider they use. Organizations get stronger, identity-backed verification at the moments that matter most, powered by their existing MFA setup.

### Expected Outcome
With Proof of Presence generally available across all identity providers, organizations can consistently enforce re-authentication at critical points in the software development lifecycle. Routing verification through each team's own IdP and MFA gives security teams confidence that only authorized contributors can merge or approve code changes. This reduces the risk of unauthorized changes from compromised accounts and helps teams meet security and compliance requirements without adding unnecessary friction to everyday workflows.

The issue provides no repository files, tests, or implementation entry points to inspect. Start by clarifying the product scope for Proof of Presence across Okta, Ping, SAML, and OIDC-compatible identity providers; done means re-authentication works consistently before high-impact actions for all supported providers.

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