* fix(workflow): draw a highlighted edge over the ordinary ones
An edge's z came from the nesting depth of the container it belongs to, and a
highlighted edge kept that depth like any other. A line one level deeper
therefore sat above it and painted straight through the highlight, cutting it
in half wherever the two crossed.
Give a highlighted edge — selected, or connected to the selected card — the top
tier of the edge band instead. Depth only ever ordered edges against each
other, and once the user has picked one out, being drawn whole matters more
than which container it came from.
The tier stays inside the band, below the cards, deliberately: highlighted
edges were elevated over the cards once before and drew across the chrome of
their own endpoints. A line belongs behind cards, knobs and the action-bar
swell whether or not it is highlighted, so ordinary edges give up the top of
the band rather than the band being widened into the cards.
* fix(workflow): elevate the connection preview edge with the rest
It renders highlighted — its data carries `isConnectedToSelection` — but it was
the one call site left taking a depth tier, so the line being drawn could be
crossed by an ordinary edge in a deeper container. Highlighted now means
elevated with no exception.
Also drop the export on the highlighted tier: nothing outside the module reads
it, and the band's tiers are an implementation detail of `getEdgeZIndex`.
* fix(workflow): give the edge highlight one definition
The z-index elevation I added checked canvas selection only, while the edge
darkens for panel focus too — a block open in the editor lights its edges, and
those stayed depth-tiered, so an ordinary edge could still cut through the
highlight. The bug I set out to fix, on the path I had not covered.
The condition already existed in two places and the second one carries a comment
saying it must mirror the first exactly, because a knob checking fewer
conditions than the line leaves a dark line running into a light knob. Adding
the z would have made a third copy, and the finding here is what the third copy
gets you.
One predicate now, in `edge-highlight`, used by the line, the knobs, and the z.
The canvas subscribes to the panel store rather than reading `getState()`, since
the z has to be recomputed when the open block changes.
Waleed
e56b28857c