Unify CefWebviewUri and InlineHtml into a single WebviewSource enum component, eliminating the dual-component inconsistency where both existed on the same entity
Add ResolvedWebviewUri internal component as a resolution layer between user-facing source and CEF
Support dynamic reload: mutating WebviewSource at runtime automatically navigates the existing browser via browsers.navigate() without recreation
Inline HTML is served via cef://localhost/__inline__/{id} with automatic cleanup on entity despawn
