Update API specifications with fern api update

[github-actions]

Update API specifications by running fern api update.

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Note

Medium Risk
Webhook event type string renames are a breaking contract change for subscribers and generated clients; org boolean defaults were removed from the spec, which may shift SDK defaults.

Overview
Regenerates openapi.json via Fern, expanding the public contract rather than changing runtime code in this diff.

Webhooks: WebhookEventType values switch from dot-separated names (e.g. model-connection.create) to colon-separated ones (model-connection:created). New structured types WebhookEvent, WebhookEventCollection, and WebhookEventOperation describe outbound webhook payloads.

Realtime / sockets: Adds diagram content socket messaging—client subscribe/unsubscribe on landscapeId / versionId / diagramId, server diagram-content-broadcast with full DiagramContent, plus SocketMessages / SocketMessageType wiring. DocumentBroadcastType and QueryBroadcastType enums (added, initial, modified, removed) support broadcast semantics.

Other schema tweaks: DiagramContentNullable (content or null); Organization, OrganizationPartial, and OrganizationRequired no longer declare OpenAPI default: true on aiFeaturesEnabled and oauthLandscapeWriteEnabled.

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