fix: top-bar polish — lights on the pill line, rename escape hitbox, inert phase pill, chrome carve-outs

Traffic lights (owner report: 'way too low, not aligned with the phase pill'):
measured in the running app — circles centered at 30.75pt vs the pill box's
29.25pt (band 0-59.5, pill box 19-39.5, pill ink 28.75; uppercase glyphs sit
high). trafficLightPosition y 24 -> 22.5 lands the circle centers at 29.25,
exactly on the pill. Owner confirmed aligned after this change.

Rename escape hitbox (owner report): entering rename was already width-of-
title only, but the editing input spanned flex-1 so clicking the rest of the
bar stayed inside the input. The input is now shrink-to-fit
([field-sizing:content], min 8ch / max 70%) and any mousedown outside the
input blurs it, running the existing onBlur commit path; the header drops
lh-drag while renaming so the drag region cannot eat the escape click.
Verified: click-away commits (exactly one PUT), Escape discards, Enter
commits.

Phase pill is pure decoration (owner report: 'should not be interactable
in any way'): no tooltip, pointer-events-none, select-none — part of the
drag surface instead of a carved-out target.

Graph chrome was unclickable in Electron (owner report): home.tsx's
floating drag strip underlays the z-10 controls row, and Electron's
app-region mask ignores z-index, so the region ate their clicks (plain
browser unaffected — DOM hit-testing is fine). lh-no-drag carve-outs on
the chrome row and the node detail card (it is placed imperatively
anywhere, including the top strip).

LhMark home link now mirrors the ghost toggle: same size-9 chip geometry
and hover:bg-accent treatment.

components/graph-view.tsx

@@ -969,8 +969,12 @@ export function GraphView() {
 			    without shifting its siblings — every button is 44px tall,
 			    top alignment pins the row. Coverage renders even when the
 			    graph is EMPTY — an empty graph with unextracted sessions is
-			    exactly when it matters (extract → the graph gains nodes). */}
-			<div className="absolute right-3 top-3 z-10 flex items-start gap-2">
+			    exactly when it matters (extract → the graph gains nodes).
+			    lh-no-drag (2026-09-17): home.tsx's floating drag strip
+			    underlays this row — Electron's drag mask ignores z-index,
+			    so without an explicit carve-out the controls were
+			    unclickable in the desktop app (owner report). */}
+			<div className="lh-no-drag absolute right-3 top-3 z-10 flex items-start gap-2">
 				{!isEmpty && (
 					<>
 					{/* Search — its own container (icon + input + no-match note). */}
@@ -1055,7 +1059,10 @@ export function GraphView() {
 					// Positioned imperatively in the layout effect above; hidden
 					// until placed so the flip never flashes in the wrong spot.
 					style={{ visibility: "hidden", left: 0, top: 0 }}
-					className="absolute z-10 w-80 max-w-[calc(100%-1rem)] rounded-xl border bg-card p-4 text-left shadow-lg"
+					// lh-no-drag: the card is placed anywhere on the canvas —
+					// when it lands in the top strip it must stay interactive
+					// over home.tsx's drag surface (2026-09-17).
+					className="lh-no-drag absolute z-10 w-80 max-w-[calc(100%-1rem)] rounded-xl border bg-card p-4 text-left shadow-lg"
 				>
 					<div className="text-sm font-medium leading-snug">{selected.node.name}</div>
 					<div className="mt-1 text-xs leading-relaxed text-muted-foreground">{selected.node.statement}</div>