capture Categories
Mirrors InspectorSnapshot.captureCategories -- the set of capture categories the host enabled at DevConsole.initialize(). InspectorDataSource already empties out the lists a disabled category would otherwise populate (e.g. an empty sockets when neither SOCKET nor MQTT is enabled), but that alone only produces an empty state, not a hidden surface -- the helpers below (captures, visibleObserveTabs, visibleDestinations) are the one place that turns "this category is off" into "this tab/destination does not exist right now", so every caller (tab row, bottom nav, section gating) reads the same gate instead of re-deriving it.