D240 — A selection hidden by a filter stays selected, the graph draws none

Decision. When a Type or Status filter hides the selected concept, the selection stays: the URL keeps concept= and the Inspector stays open. The graph treats it as no selection: the filtered set is drawn at full colour, with no labels and no signals, and the camera returns to the pose saved before the focus. Clearing the filter, or re-including the concept, focuses it again. When the selection is visible, its neighbourhood (the kept colours, the labels, the signals) is always the visible neighbourhood, never a neighbour the filter hid.

Why. Filtering is a view operation. Before this, the graph kept the hidden selection as its focus: every visible node receded into the canvas and the old neighbourhood's names floated over nothing, so the graph looked empty. The cost is that the Inspector can show a concept the graph does not draw.

Alternatives rejected. - Clear the selection when a filter hides it: the reader loses their place, and the cleared concept= adds a history entry they did not ask for. - Keep the hidden node drawn despite the filter: the filter would no longer mean what it says, and the visible count would disagree with the canvas.

Consequences. The fix lives in GraphView.tsx: an effective selection (selected unless hidden) drives the colour and the selection effects, and the selection effect depends on the visible set. It relies on being declared after the visible-set effect, so it re-runs after setData in the same commit; a comment beside it says so. LivingScene needs no change: an absent id already hides the ring and stops the camera follow.